hey, congrats, looks cool! I would suggest that the map demo connect users to each other rather than forcing them to invite others (though you should keep that potion)... that way people can use it without going through the hassle of inviting a friend.
Typo on the front page does not inspire confidence (but it happens to the best of us.):
"ThatsMyMouse is live! You can now add ThatsMyMouse to you site. Let us know what you think in our blog."
Aaaaand wtf is with the creepy pics of young girls looking into the camera all over the site? This is a good idea* in need of a GUI designer and a copy writer.
*If it's good enough, the rest of this sentence may not matter.
Oh, and I'm not all piss and vinegar: the chat is pretty smooth and nicely implemented.
I launched thatsmymouse.com this morning. Mashable posted a very positive review; http://mashable.com/2008/01/31/thatsmymouse/
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