Well, the OP did say he would tally everything up... Then told us to copy and paste the list from the person above you. It's confusing! I think O-D-C's post is the last one that has everything.

EDIT: Once again, the list up to Nordlead (I think). ^_^

* Super Smash Brothers Brawl - 6
* Mario Kart Wii - 5
* Halo 3 - 3
* Killzone 2 - 5
* Resistance 2 - 3
* Soul Caliver 4 -
* Guitar Hero (series) - 4
* Rock Band (series) - 2
* Call of Duty 4 - 5
* Call of Duty: World at War - 1
* Motorstorm -
* Motorstorm: Pacific Drift - 1

Phoenix, which COD? There's two here, you know. I'll add that in when I know. =)

* Super Smash Brothers Brawl - 7
* Mario Kart Wii - 5
* Halo 3 - 3
* Killzone 2 - 6
* Resistance 2 - 3
* Soul Caliver 4 -
* Guitar Hero (series) - 4
* Rock Band (series) - 3
* Call of Duty 4 - 5
* Call of Duty: World at War - 2
* Motorstorm -
* Motorstorm: Pacific Drift - 1

plan to get MKwii later,
SSBB can get laggy sometimes, i only have two friends with "no" lag
Just got RB2 and loving it
starting to get bored of KZ2...

I "heavily" play killzone 2, resistance 2, and motorstorm pacific rifit currently. And I also am loving the new expansion for unreal 3 and am currently satisfying my inner trophy whore with this game.

* Super Smash Brothers Brawl - 7
* Mario Kart Wii - 5
* Halo 3 - 4
* Killzone 2 - 6
* Resistance 2 - 3
* Soul Caliver 4 -
* Guitar Hero (series) - 5
* Rock Band (series) - 4
* Call of Duty 4 - 5
* Call of Duty: World at War - 2
* Motorstorm - 
* Motorstorm: Pacific Drift - 1

And this is really the worst way to go about doing this seeing as there are over 50% PS3 owners and much less Wii and 360 owners.  

* Super Smash Brothers Brawl - 7
* Mario Kart Wii - 5
* Halo 3 - 4
* Killzone 2 - 7
* Resistance 2 - 4
* Soul Caliver 4 -
* Guitar Hero (series) - 5
* Rock Band (series) - 4
* Call of Duty 4 - 5
* Call of Duty: World at War - 2
* Motorstorm -
* Motorstorm: Pacific Drift - 2

You're welcome, Avarice. =)
Phoenix, I know you aren't online, but I'm saying this again so I won't forget; I need to know which COD because as of now, that vote hasn't been counted.

* Super Smash Brothers Brawl -
* Mario Kart Wii - 1
* Halo 3 -
* Killzone 2 -
* Resistance 2 -
* Soul Caliver 4 -
* Guitar Hero (series) -1
* Rock Band (series) -
* Call of Duty 4 -
* Call of Duty: World at War -
* Motorstorm -
* Motorstorm: Pacific Drift -

* Super Smash Brothers Brawl - 7
* Mario Kart Wii - 5
* Halo 3 - 4
* Killzone 2 - 7
* Resistance 2 - 4
* Soul Caliver 4 -
* Guitar Hero (series) - 5
* Rock Band (series) - 4
* Call of Duty 4 - 6
* Call of Duty: World at War - 2
* Motorstorm -
* Motorstorm: Pacific Drift - 2

Oh I get why Yo _John mention the whole "More Sony On this site" thing
It would seem that so far KZ2 gets played more than Halo 3

* Super Smash Brothers Brawl - 7
* Mario Kart Wii - 6
* Halo 3 - 4
* Killzone 2 - 8
* Resistance 2 - 5
* Soul Caliver 4 -
* Guitar Hero (series) - 6
* Rock Band (series) - 4
* Call of Duty 4 - 6
* Call of Duty: World at War - 2
* Motorstorm - 1 (Unless CGI meant PR)
* Motorstorm: Pacific Drift - 2

Once again, I think this is everything. Just to clarify for the OP, I have only voted once, I'm just trying to help keep everything tallied up. I dunno if you wanted us to make a list and keep adding to it or if you wanted us to just say what we still play, but whatever. ^_^

* Super Smash Brothers Brawl - 7
* Mario Kart Wii - 6
* Halo 3 - 4
* Killzone 2 - 8
* Resistance 2 - 5
* Soul Caliver 4 -
* Guitar Hero (series) - 7
* Rock Band (series) - 4
* Call of Duty 4 - 6
* Call of Duty: World at War - 2
* Motorstorm - 1 (Unless CGI meant PR)
* Motorstorm: Pacific Drift - 2