It’s an excellent name. It’s not supposed to be proper grammar—that’s part of the playfulness of it. It’s not a sentence, it’s a name. What you’re saying is like saying ‘Flickr’ isn’t a word.
Yes. We used to get hundreds of letters from English teachers pointing out that the correct phrasing was "You Have Mail". In fact, at one point, the AOL welcome screen said "You Have Mail", even though the voice still said "You've Got Mail".
But, like "idonethis", and like you, we thought our version was just.. stickier. And it stuck.
Downvoter, this was my point: Sticky beats grammar. (See also: Think Different.) Sorry if I was too terse to make it clear.
This is a case where a few hundred dollars on a good domain name would go a long way.