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Hi Seomvi - yes, definitely a challenging problem, especially since you're thinking preventative rather than reactive (which is very wise!). My advice would be to consider creating some form of threshold for forum content before you expose it to Google. For example, you could have a litmus test that says, if a forum thread has <500 words or fewer than 2 unique replies, apply a META NAME="ROBOTS" CONTENT="NOINDEX, FOLLOW" to the page header. In that fashion, you keep algorithms like Panda from perceiving your forum as having lots of thin content/low value pages. For PR flow and crawl budget, I'd generally worry less. Google's gotten very adept at identifying forums, crawling them effectively, and understanding how to handle that type of content/link structure. That said, you might try using rel=prev/next to help with Google's crawling. Wish you all the best!