if you plan on going online & want graphics choose ps3 if not wii is very acceptable

For what you say, Wii ;)

If you're only wanting to play Rock Band 360 is the cheapest of all.

I would go with Ps3 for a couple reasons...

- Nintendo has met their quota for games. They do it with every system they put out. ONE Mario game, ONE Mario Kart game, ONE Zelda game, ONE Smash Bros game. And after that... nothing. No sequels. Nothing new. Dont expect much more from Nintendo.

-Ps3 on the other hand is receiving a lot of UNIQUE, NEW Ip's like Uncharted, Infamous, MAG, Heavy Rain, WarHawk, Resistance, LittleBigPlanet, etc.

-Ps3 has Blu Ray. Better graphics. Is a true next gen system, while Wii is basically a last-gen system that has only succeeded due to gimmicky controller

I think you may be a more social gamer. Are you planing to invite non-gamers friends and girls over? They will love to show up and come back for some more. So I say the Wii.

Thinking longterm, both consoles will be around for a while. The PS3 because it is more powerful and the Wii because its marketshare, so games will keep coming.

Do you prefer cutting edge graphics and playing on your own? Forget about the Wii and get a PS3.

Yes, because Nintendo only has 4 franchises....  Just because you don't know anything about Nintendo games doesn't automatically make PS3 games better, either in the absolute sense or for the OP. 

OT: as others have said, unless you are a huge RB fan don't make the decision based on that one game alone, look at the other games that you might play on the two systems and make your decision based on which system has more games that you like, assuming that money isn't an issue

rockband does not have good graphics even on an HD system. The biggest thing is whether or not your going to be going online to get DLC. If you are Get an HD system of not then take your pick. Also you could get a 360 Arcade and save your self $50 or so and also have the ability to get DLC

well one advance its u can get DLC for the ps3.
faster and easier.
and yes the ps3 graphics are better. but for a game like rockband its doesn't really matter.

If you like the games on Wii better then get the Wii. The PS3 has more future titles coming though so keep that in mind.

lol Gearbox, don't take his opinion seriously since it's pretty much pro-PS3 and anti-non-PS3 lol. And considering it's pretty false in what he just said.

That being said, I think you just answered your own question.