"The only downside is ..."
You forgot about the terrible interface at 10ft and the need to fiddle with settings on every game that you want to play. All three of the current consoles still utterly destroy the PC in terms of letting you pick up the gamepad and get in to playing a game optimized for your specific platform as quickly and painlessly as possible.
Yes, 1080p/60 on the PC is very nice and to play on in the living room. That quality comes with needing to touch a keyboard and mouse, hop on the internet and figure out what setting you need to twiddle to turn of the enforced 30fps cap (Alice), figure out why your video card is enforcing 24hz output (Crysis), figure out which setting is causing your occasional loading stutter breaking your perfectly smooth 60fps with long 1/10 second dropped frames (Bioshock), enforce launching straight to the game instead of a launcher that requires mouse input (Skyrim, Saints Row), shut the game entirely down and start it back up because you let your gamepad go to sleep (Tomb Raider). Oh, and of course Steam wants you to enter your password again because you signed in to buy something on your other PC. This list can go on for days with all the stupid little things you have to deal with before simply sitting down and enjoying the game.
Steam Big Picture wanted to fix some of this, but it did a very half-assed job, poorly remembers the 360 gamepad, and seems to have been forgotten by Valve already.