I don't know about others, but this is the first time I had heard of professional forum posting. It might be that people are just a bit skeptical? Do you have a page that assures people that you'll post real posts and not just spam? I also would like to know how you handle requests by forums that are specific to a trade or require expertise that you probably don't have (i.e. airplane engineering, professional cake decorating, etc)?
I like the little intro that you have, but I think posting examples of some of your posts may give you even more credibility.
I'd also spruce up the header, somehow the geek head on the left is not enough. I'd liven up the site with more graphics and links, but you don't need that much, just that extra bit of "umph" I guess.
Just my $0
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