Glad to see some people jumping on the bandwagon.
I made this suggestion long ago (probably close to a year at this point?) in some of the earlier PS4 threads. Everyone shat on my posts, citing that 'the most powerful console doesn't usually win'. I tried to argue it's not simply about power, as you said there is a greater confluence happening.
The industry is changing. In order to make up costs, MS and Sony want generations to last much longer like this one has. It's not just about HW performance, they are moving to a much more services-oriented model to help keep consoles alive. But they still need a fairly significant leap in performance to keep the consoles viable in terms of graphics. Obviously they can't really maintain graphics competitiveness over the long-term, but it needs to at have some significant headroom. The way to do that is to wait until there is a significant jump in tech both in terms of performance and costs. Coincidentally ... these sort of major advancements tend to happen over a longer timeline - say 7+ years ... not the traditional console generation timeline.
What we'll have available in 2014 is a new way to generate massive memory bandwidth, as well as new die shrinks for processing. It's not just about raw performance, it about performance per watt, TDP, and long-term cost scalability. Stuff like stacked DDR4 will see major cost reductions throughout the generation, etc.
The other side of this is the extra features and services. Much like the aforementioned tech, we are also seeing a confluence on that side of things. We are seeing a lot of movement on display tech (not only 4K, but HMDs), 2nd screen features, and the biggest change to television media in history. There is finally
some movement on IPTV packaging. These sort of things are going to take a while to settle out. And while they don't necessarily need to be in place for launch, the console manufactures need to at least have a relatively clear idea what sort of I/O, OS framework, and OS footprint will be necessarily to incorporate these services.
Much like the confluence of HW, this confluence of services is all pointing to 2014 as a solid time to launch a forward-looking system that will be able to utilize such features over the long haul. Consoles are no longer a sprint ... they are a marathon of features.