I've been reading some old posts and saw advices about "post in forums" when you guys say "post in forums" do you mean advertise your site in forums? OR just post messages in forums and have your site in the signature?
You probably wont get a lot of high quality signature traffic unless you are a beast of a poster. On top of that the attrition rate for signature traffic is extremely high. This means you might pick up some traffic the same day you are making posts but if you stop your posts quickly get buried and the traffic flow stops. Even with the high attrition rate I would definitely say the quantity and quality of traffic from forums is much better than 99% of directories. In terms of SEO I would say forum sigs do have some value if you are posting in forums within your industry. The problem with sigs is you have very limited control. Sure you can plug in maybe 5-10 links with anchor text but those links are displayed on every post whether it is targeted or not. It would be much better if you had the option to modify your sig when making a post. That way you could link to a page or two within your network that best matches the topic.