I'll tell you what, I'll make 5 posts on your forum if you make 10 posts on mine. Then I'll make 10 on yours and you'll make 20 on mine, and so forth (it's not an equal number of posts because I'm older than you and you should respect and revere your elders). We keep doubling the number of posts, then after a few weeks we should easily have millions of posts. That'll be awesome. Our forums will rule.
Remember though, your posts all have to be relevant and high quality. I will post lorem ipsum placeholder text in your forum, which is gibberish, but the posts will have my name on them, and I'll stand behind them, 100%
I love this plan, let's get started.