Ok here are the lists of  my top 5 games on the Nintendo Wii, PS3 and XBox 360. That have been released. Games to be released do not count.

Nintendo Wii: SMG,SSBB,SPM3, Resident Evil 4 WE and Wii Sports.

PS3: Uncharted, R&C:ToD, COD 4, Assassins Creed and Guitar Hero 3.

XBox 360: Mass Effect, Bioshock, COD 4, Gears of War and Halo 3.

Wii (my only system):
1. SSBB
2. Wii Sports
3. Fire Emblem: Radiant Dawn
4. SMG
5. No More Heroes -----> Zack and Wiki.

Edit: No More Heroes changed to Zack and Wiki.

Nintendo Wii

1. Zack & Wiki
2. Super Mario Galaxy
3. Metroid Prime 3: Corruption
4. Resident  Evil 4: Wii Edition
5. Rayman Raving Rabbids

XBox 360

1. Bioshock
2. Gears of War
3. The Orange Box
4. Geometry Wars
5. Dead Rising

Playstation 3

1. Uncharted
2. Burnout Paradise
3. ...Do I really have to pick 5? Those are the only two games I've played on my PS3 so far that I actually enjoyed and I didn't even like Burnout that much.

Damn, I totally forgot about Zack and Wiki while making this list! Maybe I'll bump off No More Heroes for it

That's alright, I forgot about Super Smash Bros Brawl. >_>

It's weird, I'm struggling to make room for my Wii top 5 as there are about 10 games I would to put on there, the 360 fit just right, and I can't even think of 5 PS3 games I even enjoyed playing.

Twesterm nah man you do not need to pick 5 games.
Assassins creed and COD 4 would be many people's popular picks in their top 5 PS3 games that have been released. PS3 top 5 list will be significantly different in a year's time when the best games are to be released on the PS3.

I actually wasn't in love with CoD4 and played it on the 360 and not the PS3. I picked up Assassin's Creed this weekend with my massive trade in but I still haven't gotten around to playing it. I've been busy with Brawl and Lost (worst game this gen).

Xbox 360
1. Lost Odyssey
2. Eternal Sonata
3. Blue Dragon
4. Gears of War
5. Bioshock


Wii
1. Super Mario galaxy
2. Metroid Prime 3
3. Super Smash Bros Brawl
4. Zack and Wiki
5. No More Heroes

i only own 5 games (and wii sports) but i have owned a total of 9 (and wii sports).

so, of my 5 games:

1. galaxy
2. zack and wiki
3. power pros baseball
4. truama center: 2nd opinion
5. super paper mario

1. Wii sports
2. Galaxy
3. Metroid
4. Tiger Woods 07
5. M+S at Olympic Games