I've just spent the last hour or so reading the posts relating to phpbb v vBulletin here. The main issues everyone seems to have with phpbb are security/spam related.
I have phpbb installed on my website and I have added a ton of mods to it so that over time it has become exactly what I want and gets little or no spam. So I'm kind of reluctant to switch over to vBulletin unless the benefits outweigh the negative side effects of a switchover/cost etc.
The reason I feel I should switch is because after almost a year the site does not rank very high on Google and after a lot of research and reading a lot of posts I have come to the conclusion that most people think phpbb sucks in the SEO dept. Is this the case? I've Googled the bejaysus out of optomising phpbb for search engines and done all the reccomended things like getting rid of session ids etc, but the traffic to the site still seems to be a bit low. Does anyone have an opinion on this?