The OP says rumors and maybe "leaks", but which are true?
If you build your speculation on rumors, it's a house of cards and with one wrong rumor or "troll" used in building your speculation, it can totally collapse. For example; the OP has a quote that the Video output will be 1080P with only a HDMI port; this is obviously "logically" wrong.
The AMD GPUs include video output hardware and they use Display Port that can be converted to HDMI. Display Port can support 4K resolution, multiple monitors, directly drive LCD panels including provide power which will be needed for head mounted glasses and more. The Xbox 720 powerpoint listed Display Port and some of it's possible outputs for the Xbox 720.
So Everyone going AMD GPUs is probably using AMD's display port video output. To believe Sony would strip out the AMD video out and not support 4K is deluded or
trolling. So should we believe the OP in it's entirety? NO, but even trolls put known or accepted facts into a post to make them believable. In this case I believe 2 gigs maybe 4 but it's not locked as GDDR5 as other rumors have DDR4 being used and in those rumors PS4 is being delayed till 1st quarter 2014 because they want to include stacking and custom designs for DDR4 to support Fusion or Intel CPU/GPU which require very high bandwidth and short traces on motherboards. Which rumor do you believe? This might apply to the Xbox 720 also as rumors have them using a nearly identical Jaguar/GPU core which should use the same memory interface.
Lots of very bright people with more insider information are speculating about next generation and many are getting it wrong. I'm also speculating and for sure some of what I post can be wrong. For example:
Charlie at SemiAccurate predicted the PS4 would use the Intel GPU -
Larrabee GPU then early this year had a news article stating that the Xbox 720 main silicon "Oban" taped out and started production Dec 2011 with 10,000 SOI wafers @ 32nm and that he was 99% certain that it was a IBM Power ISA platform. Both above are likely wrong but were good speculation at the time.
Oban as a Xbox 360 refresh not Xbox 720 was first proposed in the Simi Accurate forum by East of Eastside but there was no support for this. I also had issues with the Xbox 720 being 32nm and too early for a anything but a 6000 series GPU. Between 6000 to 7000 the 7000 is 1.6 times as efficient and between 7000 to 8000 another 1.2 times. So using 32nm and giving up nearly 100% (Double) the performance increase at no additional cost just to be 6 months to a year earlier than PS4 did not make sense.
I found a
Linkedin profile for a IBM employee that was assigned to work on game consoles. In it work done and completed for a 32nm Xbox 360 game console was mentioned. Since the last Xbox 360 refresh was the 360S @ 45nm this proved a refresh @ 32nm was coming this year and supported Oban was a Xbox 360 refresh if the rest of Charlies post was accurate. There was also that the Xbox powerpoint had a Xbox 361 refresh scheduled for 2012 also.
So SUPPORTED speculation not possible when Charlie made his guess has ME guessing that a Xbox 360 refresh is Oban and coming this season. From here, speculation gets wilder with more assumptions.
1) From only a 2 year old Xbox 720 powerpoint (Edit: lead time from initial proposal to build is min 1.5 years so comments I've heard about "in 2 years it could have changed" don't take this into account. 9/2010 (powerpoint document) and 12/2011 tapeout does not give enough time for a redesign.) the Xbox 361 has HDMI pass-thru which implies low power modes. This requires a more modern GPU and logic to control the CPUs power and clock speeds as well as GPU power. This is supported by newer AMD GPUs but not the CPU and GPU @ 45nm in the Xbox 360S that hardware emulated the even older Xbox 360 CPU and GPU.
2) Within 18 months power modes will be required by California for Game Consoles. So either a total redesign occurs for both PS3 and Xbox 360 this 2012 refresh @32nm or at the next refresh for 22nm (both Xbox 360 and PS3 are getting a refresh this year and I guessed that a month ago before the FCC listing or the Xbox 720 powerpoint which I also found and posted to NeoGAF). I'm not trying to boast but when your attacked it's justified to bring up that you do the work to support your speculation.
For the 360 to support HDMI pass-thru and power modes a major rewrite for the OS is required. It will require newer CPU, GPU and support chips. For instance, memory will require some method to keep it active with power at all times to support standby and at least one CPU active and monitoring the HDMI video stream to intercept key parts of the data stream included in video and to monitor for a start command from keyboard or possibly voice recognition.
And another level of speculation builds on the above is that it will be easier this time to software emulate GPU and support chips rather than try to hardware emulate like they did with the Xbox 360S.
Building on that, PS3 refresh if it has a depth camera and HDMI pass-thru will likely do the same with the 1PPU3SPU multi-processor architecture mentioned in the Sony 2010 patent (Digitimes PS4 rumor 6/2011 and Sony depth camera patent Feb 2012).
Building on that since both are emulating and a Xbox 360 refresh hardware only needs to add 6 SPUs to emulate a PS3 why don't they share the same core Silicon to reduce costs.
It's a house of cards with everything built on multiple levels of speculation. The further you go in the chain the higher the probability of my being wrong. For instance both Xbox 720 and PS4 need to be using AMD X86 and GPUs/support chips and both would want to support BC to support parts of my speculation.
Also in the Linkedin IBM employee post is this; "- Led an
international team to complete the design hardware characterization on a 32nm project." This must be Oban @ 32nm and for the first time (remember this employee did primarily game console and WiiU is at 45nm) is an "International Team" and Oban besides being a Scotch from the Oban region of the UK is a large blank oblong
Japanese Gold coin. Yes I know very weak to support such a large speculation but it's all we have.
The above is an example of my guessing which may be more accurate than professionals only because I waited for information to support my speculation contrary to the opinion that I wildly speculate with no support.
1)
microsoft-sony.com
2)
digitimes PS4 rumor (Must be a PS3 as it's to be released 2012)
3)
Xbox 720 powerpoint Xbox 361 if Oban 12/2011 was already in the pipeline when the powerpoint was made 9/2010
4)
This patent and the timing in both filing and publishing XTV game support for Commercials on TV.
5) Both ps3 and Xbox 360 refresh must have a price reduction built in to allow a price reduction when the PS4 and Xbox 720 are released. This is already possible for the Xbox 360 but the PS3 would NEED a massive redesign to put both CPU and GPU on the same silicon.
6)
Sony 2010 1PPU4SPU patent
7)
Elizabeth Gerhard's Projects (IBM employee) and an International project involving the Xbox 360 @ 32nm and NO design work for a PS3 refresh at 32nm
8) Oban =
large blank Japanese Coin => is Oban for both the PS3 and Xbox 361 (Microsoft making the chip for Sony)
9) Both having browsers at the same time for the first time ever and both have a refresh at the same time for the first time ever
10)
Sony depth camera patent (Timing, 9/2011 & again 2/2012)
11) Khronos Openmax 1.2 (Supports Gstreamer-openmax and camera, second Khronos Pdf mentioning Augmented Reality starting Sept 2012 leveraging the browser libraries
Read #10 above and then look at the following picture and the description of the Bat in the Xbox 720 powerpoint.
Many of the accessories can be used with the PS3, PS4, Xbox 720 using blu-tooth but not with the Xbox 360, at least the pre 2012 refresh. Some standard for accessories is likely.