I enjoy both console and PC gaming and my preferences on which I love more change all the time.
CONS of PC
Cost - It can get pretty expensive but can be cheaper if you make it yourself and isn't all that hard nowadays to do so
DRM - Digital rights management has all sorts of ways to annoy you, Only allowing you to install the game on one computer at a time to having to be constantly connected to the internet even if you're playing a single player
Games A lot of developers don't bother porting there games to PC e.g Red dead redemption, sometimes when they are ported there terrible or can take months sometimes years to get ported to the PC
Over-thinking This one is more of my trait but sometimes all I can think of is the games frame-rate and if I'll need to make more improvements to my PC
Cons of consoles
Online services Sometimes Games will loose there online support and servers will close down, which includes DLC for games that don't even have multilayer online.
Disk While I prefer physical media if that disk gets too damaged no more game for you
pro's of PC
Massive library of games - So many games on the PC !
Smooth graphics Even if there's a game you can get because your computer isn't up to it, in the future you will upgrade your computer and be able to play the game at it's best in term of graphics and framerate.
Supreme control A comment that comes up a lot is (I don't like using a mouse and keyboard) most games let you use a controller and you can emulate a keyboard via the controller with certain programs. Not to mention there's more third party controllers for the PC than any other console
RTS This genre is best on the PC because of it's keyboard and mouse, the PS3 and I think the 360 can have keyboard and mouse input yet developers never bother I know a few games that allow you to use the mouse and keyboard (unreal tournament 3)
Mods A lot of games on PC can be modded from level editors to full blown control of pretty much everything. The elder scroll games are good examples of mods.
Indie games Minecraft shows us how popular indie games can become and be taken of the ground.
Patches Pc games can be patched immediately where's I believe on the PS3 and 360 platforms there has to be a wait.
Cost A lot of the time PC games will be cheaper
pro's of consoles
Games By that I mean some games never get ported to the PC and nowadays there are more exclusives on PS3 and 360 to look forwarded to than PC
Plug in and play Although some games now need to be installed you can slip the disk in and play most of the time.
No worry's You need to worry if the game will run or not of course sine there built for the hardware
'Couch co-op' I know pc can do split-screen however now-days a lot of developers don't use it. Borderlands for instance on pc didn't include it,Yet the console version did but still retained lan and online. Choice in my opinion is better. split-screen is great since you or your friend don't need to buy another copy and with bigger screens split-screen doesn't seem all that bad, Nothing beats couch co-op imo
Bigger screen Now some may argue they have there computer set up on there huge 52 inch tv screen others don't. I don't think the majority have there pc hooked up to huge tvs and it's far more common that the game system is
Now the cons and pro's were all thought up that the users was a law abiding citizen and didn't put emulators on there PC systems or Game consoles
At the end of the day it doesn't matter as long as the gamer has fun the console/PC achieved it's purpose.
I think there both great but sometimes I can't help think think that both systems will suffer with some of the ******** the gaming industry has been throwing in our faces such as greedy on disk dlc and restricting with what we are allowed to do with the game once we have purchased it.