I would prefer if people put them on both with a link back to Commons or the Wikimania 2008 website. As most Commoners will tell you, things tend to get more visibility on flickr.
-- Casey Brown Cbrown1023
Visibility to whom? I don't suppose too many people who aren't interested in Wikimedia would go looking for those photos. It's just an extra place to look for photos, and I don't see the point.