If you look at the 'This week I have mostly been listening to/watching...' forum, there is a really useful thread that people keep pretty up-to-date with their current listening. I've discovered a few things from other user's posts.
Dont know if you've ever used it, but last.fm is good in this area. You put the kind of music you like in to your profile, then it can suggest other stuff you might like. Theres an iPod Touch app for it which is the best way to listen in my opinion.
I really can't put my finger on my musical taste Big Chris... i like music with energy, but not to say it has to be upbeat. i think i can hear if somebody trying to sing emotionally is faking it.. and it puts me right off there music.
examples of stuff i like are:
Adele
Michael Buble
Red Hot Chilli Peppers
all of the Fabric live mixes
Phil Collins
Chevelle
Fat Freddy's Drop (anyone who hasn't heard these guys needs to have a listen)