Hi guys i heard that posting in forums with your url in your signature gives you backlinks but im posting in forums daily and im not getting any backlinks i use this tool to check http://www.domain-pop.com/
Did you check in Yahoo. Plenty of links to my Add URL website show up when I look using Yahoo SiteExplorer. Google doesn't update links as often.
In my google sitemap acc..i see a lot of links from some forums including this...may be some forums share the google juice....Google teakes much time to know about new links and also takes more time knowing that links r deleted now...
for you to get backlinks, the forum in which your posting should be indexed in Google and then the thread as well to get some good PR. Moreover links takes time to show up in Google. Relax keep posting in relevant forums and threads and your links will be updated.
Forum signature links are very poor, so if your posting just to obtain backlinks or PR i would find another method fast as your just wasting your time.