Here's a few considerations to...well, consider.

The age of the forum -- I see by all the start dates of the posts, it looks like the forum is only as old as March. Yes, I know pages get listed reasonably quick in Google. But in many cases it still takes some time to be 'found'. Sometimes it has to do with the crawl rate that the bots visit your site.

Did your site change frequently before? The more frequently your site changes with dynamic content, the bots will come more frequently.

Now that you have a forum, and as long as posts are being added regularly, the bots will become regulars as well.

Also, not to fire up a debate, page rank (google) needs time to move downstream to new pages linked from the established pages that have some juice.

Finally the url issue as mentioned before. Just to clarify, search-engine friendly urls will perform better. The urls you have now can and will be indexed. But if you can shrink the url's down to rich keywords, the better off they'll be. Every bit helps.

How to do that? What forum software are you using... Go to their website's help files, support forum, or what have ya's, and look around for a plug-in that will do that. Chances are someone in their user community has already identified the issue and found / created one themselves.

Give it just a bit more time, the forum will take off.

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