m vs. M
Well, seeing as a lowercase m denotes milli, I believe this is quite a fair price... I'd buy twitter for 700 millidollars ($0.70!) too! It's worth nearly that much.
Why the hell would anyone pay $700M for a site that doesn't make any money and probably never will, though? This defies logic, I thought the dotcom bust was over long ago... or is this dotcom2.0?