Forum Moderators: phranque
According to GoogleGuy, Google is now pretty good at spidering dynamic URLs, so there's little motivation for doing that for Google. I've found this to be the case, and as of the last update have over 2000 forum pages in the index. (I did add one simple hack that disables SID usage for GoogleBot)
There are alternatives - do a search for static pages on the phpbb2 forums, and there are full details on how to make your pages static.