How do you play these files?
I used the Ogg Codecs for Windows from http://xiph.org/downloads - just use Windows Media Player as you would with an mp3 etc.
Favourites from original SoaSE
1) Advent Quiet 2: great music to unwind at the end of the day.
2) Battle 1.ogg: classic battle anthem, I can just imagine some mighty fleet engagement.
3) Trouble 7.ogg: requiem style, envisions the aftermath of a Vasari raid.
I think that Vasari had the best original anthem, although I think they could have upped the tempo a bit.
From Rebellion, I would say the Vasari & Advent Rebels have some really good tracks.
Halos has a good point though, a lot of the new music (eg new TEC ones) I've not actually heard in game.
It would be nice if the first track that was played was one of your faction's anthems - just to add some context.
The "nnnn Quiet n.ogg" tracks are good, but can get a bit generic, especially now that each race has split.