It's been a bit of a revelation. It's a legal download service; the prices fluctuate according to the album's popularity, so new releases are a bargain. Also, every now and then they have a day when they'll double any credit you add to your account, so when I added US$25 I got $50 of downloads.
Just got home to find the new Wheat album (whoo!) for $1.75 (about 60p after the discount) and a Merzbow record for 17 cents, so I thought I'd enthuse about it here. All small bands, and quite a bit not available in the UK, but good if you've quit emusic and want to download legally and cheaply through a small website.