Speaking of which, why didn't you mention Guitar Hero in your long post/rant? It basically made a genre
Because I'm a hypocrite, thats why
But seriously, didn't think of it. thats a good suggestion. (I always threw it under "rhythm game" next to Dance Dance Revolution and Beatmania, both of which had their own unique controllers and all that jazz before guitar hero did. But since they are both 90s games, I would say that guitar hero is the "best" of this decade for that category.
Anyway, your suggestions will get added shortly. And I bet you're the one sending PM's to Frogboy calling him a troll, aren't you
nah, while I do think its funny. I'd be too easily spotted to try something like that as a prank. And I've spoken him personally so I certainly wouldn't PM as a mistake.
Besides, I'm the "troll" around here, and I'll call nobody else that less I risk losing the title myself. (even though I don't deserve it as much these days as I used to. and I claimed that title as a joke which I may be the only one that finds amusing.)
Of course it's slanted. This list is entirely based off the opinons of a bunch of PC fanboys

(No offence to anyone, but seriously, if you're on Stardocks forums, odds are that most of you perfer PC games)
We don't prefer "PC games" we prefer "good games", and they just happen to be on PCs over consoles. 
Some overlooked games:
Diablo II (and expansion)
Oh JEEZ! you're right!!!! that is fail on my part! my brain threw that under '90s' game even though it came out in 2000. yeah... thats a "best of the decade" if I've ever seen one. F*** guitar hero or rockband.
oh thats nice just leave the stealth and fighting genre out the loop.
stealth is its own genre now? lol... last I checked it was at most a sub-genre of "action"
They still make fighting games?
I thought they all got consumed by the "party game" genre.
next you'll tell me "racing" is a genre. (rather than a combination of "sports", "action", and/or "simulation")
Catan (xbox live)
Hey, thats not fair. Its a port of a board game from 1995. That would open up nominations for remakes of older better games than the ones already being nominated. Its not even the best electronic version of said board game, as it includes none of the expansions, and doesn't support hotseat play. (I'm not bashing big-huge-games, they did an alright job. Just "cities3D" is much better)
** disclaimer: This post contains a lot of jokes in it. Though some of it is mixed in with serious statements. Interpret at your own risk. If you feel I made any sweeping generalisms with no basis in fact, it was likely a joke.