Credit:
Since Google owns Blogger, you'd think they would have been indexing the images all along, but alas that wasn't the case. As of this month, Google has finally gotten the Picasa Web Albums to cooperate with its indexing spiders. It had to do with a problem in the way Picasa named their folders, but all is well now.
Photos uploaded prior to August 2006 are still unable to be indexed, and there is no indication of when, or if, this will be corrected.
So if you've been dying for those pictures from the office Christmas party to be indexed, your wish will now come true.
(via Google Operating System)