Normally I don't care about backwards compatibility, but I'd be happy paying an extra $100 for consoles if they were:
a) More frequently released/updated
b) Backwards compatible
Alternatively, it would be cool if they released a 'half' upgrade, sort of how PCs upgrade a video card.
ie. Let's say 3 years from now we get a PS4.5. Similar compentents dialed up: 16GB GDDR5, boost the CPU/GPU clock speed (with the same main board and design), 2TB HDD. When you put in a standard PS4 game it would play fine since it is nearly the exact same box with boosted memory and videocard, but it would allow a mid-generation bump in performance to new games.
I'm probably way off base and there are more than likely a ton of disadvantages to this strategy, but I just thought it's a neat idea. A big reason annualized releases of phones and tablets work is because all the old apps and shit still generally works, and all the new stuff can still be mostly done on the older model (only slower). If this can't be translated to consoles, then a 5-6 year cycle will continue to be the norm.