I went to last.fm as I've had an account on Pandora for several years now (and they do a good job).

Firstly, they use the British spellings. Yep. Favourite not Favorite. Not seen very often.

So far, the features I'm seeing on last.fm are more.....elabourate than the ones on Pandora. They offer a listing of concerts for the person you're listening to and make quite a variety of suggestions for other things you might like as well.

Very nice.