Here's a link to the overhead view.
http://maps.google.com/maps?f=q&hl=e...&t=k&z=19&om=1


Where and how were you hit? I do that traffic circle quite often. The bike lane "correctly" follows the circle around but also branches right. The problem is that the circle is fairly high speed -- there are only 3 spokes off the circle, so any car bearing "right" is essentially doing a high speed banked right turn. And in the bike lane you are crossing his path if you are heading around the circle.

I ALWAYS hand signal at this circle and if it looks to me like conflict might occur I usually slow down.