Dudek

I noticed that a lot of times they don't release the most known/wanted songs by a certain band or from a certain album, like with PUSA now and when they didn't put Pork and Beans on the Weezer Red Album pack. Three of the most famous Nirvana songs from Nevermind (Smells Like Tee Spirit, Come as You Are and Lithium) didn't see the light of the day on RB yet too.

Is it because they aren't musically interesting? I don't think so. Or is it because they are holding them off for the next title in the series or a later pack or something?

Yes, they do that song.
The title is easy: Mach 5.

http://www.youtube.com/watch?v=2DILjWO7DqA

We're not, gonna maaaake it!

Venice, Italy.

The Corcovado mountain in Rio de Janeiro with the Christ the Redeemer statue and all.

Not the original (SNES) ones, only the N64 versions.

No, DLC from GH3 won't work with GH:WT. That page from the link you posted had comments from users showing other sources that confirmed this. The sources were:
http://www.1up.com/do/newsStory?cId=3168347
http://xbox360.ign.com/articles/882/882888p3.html

Doesn't the homebrew channel have SCUMM already?

Just to point out that "All My Life" is on a DLC from GH3.
Anyway, that's cool of you to have brought up the setlist for those who don't know it, even though the game isn't so appealing.

He is talking about one player using 2 controllers to play. Don't you remember that feature? I do.