If you're already authenticated then it redirects to your profile page.
Just as a heads-up: Google "gittip minimum raised from" or search Twitter for the same (http://twitter.com/#!/search/gittip%20minimum%20raised%20fro...) ... there's a collective audience of tens of thousands of people, any of whom could be seeing Gittip for the first time from this submission. Linking to a blog post, even a very brief one, might be better for picking up new interest in the future.
I feel like I'm being a pain in the ass between this and yesterday's grousing over needing a Github account. Sorry about that.
Definitely could do a better job of converting traffic. Don't feel like I have that nailed yet. :-/
Any page where I can land and be asked to log in should do a better job of saying what you do, especially where trust is involved.
As soon as I saw 'log in' I immediately returned to HN comments to find out what was going on. Many people won't have that luxury, or patience.