I love the idea of winning on design - I'm a UX designer, after all - but I question the conclusion that design is how they got all those signups. They may not have been written up in TC, but they were written up in TNW. Did they get that coverage because of the UX, or did they get it because they are in a hot market?

Don't get me wrong - from what I've seen, Groove looks beautiful and well-thought-out from the user's perspective. But a beautiful and intuitive user interface won't get covered by anyone if it's in a market that no one's interested in.

Keep killing it, guys!