I just installed a change to the Forum software which changed the URLs pointing to individual threads. Formerly, they looked like this:
http://www.largeformatphotography.info/lfforum/thread.php?topic=497283
They have changed to this
http://www.largeformatphotography.info/lfforum/thread.php?qid=497283
The only change was to change "?topic=" to "?qid=".

If you created any links to any thread in web page or bookmarks, please be sure to update your links to reflect this change.

The reason was that we discovered that 'topic' may be a keyword to Google that makes it abort scans when it sees that word, which may explain why our threads aren't indexed yet, and Search doesn't really work. We'll just have to wait some more to see it this fixes anything. I hope this doesn't cause any major inconvenience.