The best way to get traffic from forums is to offer value, but that doesn't mean making 1000 posts. You need to focus on offering great and long posts that will give people an "Aha" moment.
That means avoiding 1 liners or short sentences that don't go in-depth so focus on answering the questions you have great knowledge on and avoid saying something that has already been mentioned by other members.
Don't be afraid of creating good arguments if you have to, if you think someone is talking crap let them know, that will give you a lot of attention. But never be negative or end up getting mad, make sure you have a lot of proof to backup your opinion. Always admit when you're wrong as well.
But if you want ninja then you can check out my WMS blog post here: http://www.webmastersun.com/entries...ting-Strategies-That-You-ll-Never-Find-Online
And before you can link to anything, always offer value first then share a link like I did on this post. Don't say check this out it should help, that's not offering value. Ninja
Hope that helps.