1. Civilization V (PC)
2. Assassin's Creed: Brotherhood (PS3)
3. The 3rd Birthday (PSP)
4. Final Fantasy Versus XIII (PS3)
5. Gran Turismo 5 (PS3)

1.) Pokémon Black & White (DS)

2.) Donkey Kong Country Returns (Wii)

3.) Kirby's Epic Yarn (Wii)

4.)The Last Story (Wii)

5.)Resident Evil Revelations (3DS)

1. Professor Layton and the Unwound Future (DS)
2. Epic Mickey (Wii)
3. Assassin's Creed: Brotherhood (X360)
4. Civilization V (PC)
5. Kirby's Epic Yarn (Wii)

I don't think you're thinking logically because if people own all three consoles even if they prefer 1 over the other when it comes to multi plats they should buy the best version.  I prefer the 360 but I still bought the PS3 version of Final Fantasy 13 because it was the better version.  I rarely game on the PC because I am a console gamer first and foremost but I still bought the PC version of Dragon Age Origins because it was clearly the best version and I had a system that could run it at max settings.  With the internet nowadays people know weeks and months ahead of time which versions of the games are better.  

And yes it's very common for people to prefer the exclusives from one hardware company over another but can you really claim that 1 console or the pc best games #1-5 is so good that even the 5th best game on that system is better than the competing systems #1 game?  Sure I can make a 360, PS3, Wii, PC etc top 5 lists all day but other systems are going to have at least one title that I prefer.  For example I am looking forward to the wrpg Fable 3 on the 360 and it would make a top 5 most wanted 360 list but I like the Witcher wrpg series on the pc better.  The fps killzone 3 would make a top 5 PS3 list but I like the Halo franchise better.  I am looking forward to GT 5 over any other racer at the moment etc. 

You get the picture no one system has the best fps, action adventure, racing, platformer, wrpg, jrpg etc.  

If you think so then you are hopelessly biased and probably should have just stuck to buying 1 system to start with. 

It's not about one console having the best 5 upcoming games, but the 5 games you are looking forward to most.  I have a Wii and a PS3 and I can honestly say that there are no Wii games that I am anticipating right now more than the 5 PS3 games I listed.  That can change as more information becomes available, but for right now the things I want from the system are too far away for me to really get excited about (only things that far away that I put on the list are games like Portal 2 and TLG which make up for being far away by being sequels/by the same team as two of my favorite games ever)

So yes there are situations where one can legitimately vote for games from a single system even if they own two or more.  It's all about what you're anticipating more and if your focus is on a single system most of your anticipation will go that way.

Well, you know, I own all three systems, but I'm only looking forward to 2 Wii games and they didn't make it into my Top 5, and I'm only looking forward to 1 X360 game, but it isn't in my Top 5 most anticipated games. I also anticipated some multiplatform games, but they are not among the Top5. It just has to do with personal taste in games IMO.

I agree with you, I don't have the money for more than 1 system, but if I had lots of spare cash I would likely have at least a PS3 in addition to the Wii, maybe an X360 too... but compared the the Wii not that many games interest me, so while a few may pop up now and again (in the ealy days I might have put GT5 on there being a racing fan, but it's such a ridiculously long wait I don't care anymore) my usual list would be 4-5 Wii games.

1. Gran Turismo 5

2. Infamous 2

3. The last guardian

4. Little big planet 2

5. Dead space 2 (PS3)

1. The Last Story (Wii)

2. Donkey Kong Returns (Wii)

3. Kirby Epic Yarn (Wii)

4. Infamous 2 (Ps3)

5. The Witcher 2 (PC)

Just a few comments after looking at your list. 

1.  Infamous 2 (PS3)  You think this is going to be a better action adventure title than The Legend of Zelda Skyword Sword which is possible but since this is going to be the first Zelda title made with the Wii in mind and it has the potential of receiving an overhaul similar to what Mario got with Super Mario Galaxy shouldn't you be at least a little more excited for it.  Infamous was a good game but it was released last year meanwhile it's been 4 years since a console Zelda game.

2.  Final Fantasy Versus 13 (PS3) You like jrpgs but instead of listing what many reviewers have already called a great rpg in Kingdom Hearts Birth By Sleep that comes out in September from the very same Nomura or a promising jrpg like the 3rd Birthday that will be out by the end of the year in Japan you choose to list FF vs 13 a jrpg that after 4 years still has no release date or real gameplay footage just to keep your list consistent with all PS3 titles.  Why list a far off jrpg when good ones some by the same guy who is doing vs 13 is staring you in the face?

3.  Little Big Planet 2 (PS3) Ok you like platformers but apparently just the ps3 kind since Kirby and Donkey Kong got no love from you.  But maybe you like the level creation aspects of the game which makes it unique so I can't really critize you for this choice.

4.  Killzone 3 (PS3) ok you are part of the minority that thinks Killzone is better than Halo which is fine.  Edit) But if you like both then wouldn't the Halo Reach in September of this year be a bigger deal then the Killzone 3 in 2011.

5.  Gran Turismo 5 (PS3) the choice that made the most sense to me on this list.

Every game you listed for the PS3 had an alternative that's just as good (excluding GT 5) that releases earlier.  Even if you prefer the PS3 titles over the other games I listed the fact that those good games from the same genre are releasing much sooner in many cases should mean that they would make it on to your list before those far out PS3 games.  And those are just a few examples I can think of many other titles that fit the genre of the PS3 titles you choose that are well respected and liked.