Looks like the folks at Flickr are having a busy Monday! There have been site problems all morning as they try to stitch everything back together. The top of every page currently reads “Seeing various site problems? We know! Check this forum topic.” And the forum starts with this information:

Lots of people blaming the recent addition of video support to Flickr, though there’s no evidence that this is actually related so far.

Update: The forum thread about this makes for some interesting reading for those thinking about operating a large consumer facing web application. Kudos to the Flickr staff, especially Kevin who is posting the Flickr updates to the thread, for their restraint!