Big screen TV = Monitors have better resolutions AND you can attach your PC just fine to your TV Set. Heck, my friend even used holoprojector sometimes to feel badass in some games
reclining couch = has nothing to do with consoles. See also my friend who played PC with wireless keyboard from the couch
gamepad designed for games = with limited set of buttons and possibilites than keyboard and which sucks in FPS's and can barely do RTS's at all. Gamepad is good for some gametypes but overall it is major weakness
knowing that every game should run = yeah, stability. However if the game doesn't you're pretty much out of luck.
PC:
Better controls
Allows more complex games and GUI's
King of FPS gaming
King of multiplayer
King of RTS's.
Technologically superior
Downsides:
You must update stuff regularly
Every once in a while ****ty DRM (but these are NOT the norm)
Fighting games run sweeter on gamepad, but you know, you CAN attach Xbox controller just fine to your PC so this point is null too...