I would probably call a foul if all you were doing was judging games on their graphics and nothing else, but I'm fine if you take graphics into account among other things.
But anyway, I've had experience with all three, though I only own a Wii (my family grew up Nintendo). I have to say, all three consoles do what they say they do, play video games. So they all win on that front. Me, I do enjoy the Wiimote, and even have a sensor bar on top of my computer screen *points ^ *, so I can use a Wiimote on my computer.
In terms of how easy it is to get the controller to work with your computer? I'd have to say that the 360 and Wii can tie, depending on the situation. 360, if you have a corded one, just plugs right in, but you have to buy an adapter for the wireless ones I believe (which, if I know Microsoft, is probably over priced *coughcoughwifiadaptercoughcough*). The Wii, if you have bluetooth built into your computer, then all it is is a matter of syncing it to your computer and running GlovePie. But if you don't have bluetooth, you're going to have to go out and get an adapter, which may or may not cost less then a 360 one (I got mine for $30...). The PS3 is near impossible from what I know. Well, not impossible, but my friend found it to be frustrating. Me, however, I find I'm using my old wireless PS2 controller on my compy the most.
In terms of games, that's all opinion. People do enjoy the Wii's games, others may enjoy the many shooters and what not of the 360, and people... there are to few games for the PS3 that are not on the 360 as well. But, I guess the few that are unique are good. My friend got a PS3 just so he could play MGS4, but I don't remember if he thought that was a bad reason to get a PS3 or not. I know he's not getting rid of it though (it's his only controller for his computer, and somehow I screwed it up by plugging my wireless PS2 controller in).
In terms of aesthetics of the console it self (not game graphics), the Wii does look smoother and better then the rest in my opinion. None of them look TERRIBLE, but I like the simplistic look of the Wii. The PS3 is just a black monolith, and EVERYONE can agree. The 360 is ok, but better check for the RROD. I know that is probably one of the more upsetting things you can see on your console.
As for multimedia, I can't decide between the 360 or the Wii, which one loses the most. From what I know, neither of them have multimedia, but the Wii can surf the internet (probably the best of all the internet surfing consoles with it's point and click mouse like controls built into the system it self), so I guess I'm going to have to say the 360 loses in multimedia, followed not far behind by the Wii. You guys can call a foul on that though, I may be wrong. I don't need to mention the winner though.
Speaking of internet, all three consoles have online multiplayer and whatnot. In terms of multiplayer, the 360 blows the other two out of the water. The friend code system.... I don't need to say anything. As for the PS3, I found it near impossible for me to sign up on all the accounts just so I could play TF2, although I do like that the Wii and PS3's internet stuff is free. I never really liked subscription systems, even if it's not that expensive, because it makes me feel like I have to play all the time, and I don't. As for shopping online, I have no experience with how the 360 does it, but they all have it so you can buy and download games. I'd probably have to go with the Wii on that one, cause it's simple and easy to use. Oh, and the 360 loses points for not having a built in Wi-Fi adapter.
File storage? ... The Wii loses, end of story on that one (until they come out with a hard drive for the Wii or something. You have USB ports, Nintendo! USE THEM!!).
Really, it all comes down to what kind of games you like best, because that's what a game console should be, to play games you like. If I had my way, I would own all three. Or at the very least, a Wii and 360. So I'm already half way there!
But I like to mod my consoles so I can play Homebrew and backups (it's nice not having to carry around all my DS cards... when I used to be able to do that. Can't since I got a DSi). If we take that into account, the Wii wins, as it is the easiest to mod, while the PS3 loses, cause no one's trying for some reason. 360, I don't like messing with the hardware it self (it's not a PC...), do you?