A very long time ago (more than five years, if I recall correctly), I found Pandora and liked the idea, but was disappointed at their lack of selection outside of mainstream US artists. So I wrote them an email, telling them how much I liked the service, but had never really had a problem finding new, popular music from American artists; I really wanted a way to find new music, particularly foreign stuff. I got a reply from ... it was either the guy that started the company, or someone close to that position, and he said that while they really wanted to do something like that, just being able to continue streaming popular American music was a huge struggle for them, and they didn't see expansion coming any time in the near future. After that point, I don't think I've spent more than about 10 minutes straight using Pandora. :\

I guess I worked backwards. I was a LastFM stalwart first, but after work blocked that site, I switched over to Pandora. While I'm not looking for the foreign stuff probably nearly as much as you, I did find them a helpful way to learn about lesser known non-mainstream American acts that I normally wouldn't have found. So, I think it's a grand service quite frankly. And if you know how to play it, can tweak your stations pretty well to get what you're looking for. It may not be as straight forward as lastfm's multiple artist stations they used to allow, but since they removed that years ago, I pretty much only use them on my 360 anymore.