If you haven't done so already, be sure to validate your domains and
create sitemaps and upload them to
Google and
Yahoo (Yahoo can now parse Google's xml sitemaps, so you only need the one). Within 1-4 weeks your forums should be indexed.
Search Engine Friendly URLs aren't necessary to have your forums crawled, although it may make it easier. It's not recommended on shared hosting. You can see how many pages are indexed by using
site:YOURDOMAINNAME as the url -- I have 1000s of pages indexed without using SEF URLs.
