I like both Mileena and Liu Kang's, but the SZ's is pretty bland if you ask me.
I'm not a fan of electronic music, I'm more of a death metal guy, but those tracks are OK and I'm gonna buy the CD for sure.
However, nothing can beat old school Dan Forden's themes and I'm happy there are some MK1-3 remixed tracks on MK9; if there's even a new version of the MK1 select screen I'm gonna cry for excitement!