To add to the RAM/storage thing, the fact that it's always on the internet is a big deal. Media can be streamed from central servers on-demand, so cut-scenes and things like area-specific textures are less of a big deal.

My biggest worry is the focus on the television. Do you remember the head-mounted display John Carmack was showing around E3? The guy who made it gave an update [1] on the project a few days ago, saying

  1) I am talking to Valve.
  2) I am talking to id/Zenimax/Bethesda
  3) I am talking to Epic
  4) I am talking to Crytek
  5) I am talking to Unity
  6) I am talking to several other development companies

  The extent of their relationships with Oculus varies, but
  I can promise at least a few partnerships... I am working
  with hardware engineers...

  Imagine an HMD with a massive field of view and more
  pixels than 1080p per eye, wireless PC link, built in
  absolute head and hand/weapon/wand positioning, and native
  integration with some (if not all) of the major game
  engines, all for less than $1,000 USD. That can happen in
  2013!

I think next-gen "serious" gaming will move in that direction (by all accounts the immersion is stunning), and I think casual gaming will never move away from mixed-use devices like tablets.

1: http://www.mtbs3d.com/phpBB/viewtopic.php?f=138&t=14777&...