Please review :)

I figure out relatively quickly that your forum is about collecting, but you might want to work on your tagline "For the Fans By the Fans" to see if you can make it more of a call to action/interest builder/authority builder on your site.

Since comics are so visual, you might even consider re-doing your header to include some famous DC comic shots. Consider the most famous final scenes in particular comics, etc, that people will instantly recognized and remember.

I like the posts that you are featuring on the homepage, although I would probably prefer to see them in a more condensed format where users can more quickly see everything you are featuring in scan reading.

You could play with your welcome text to image. You could enhance the text and the image to be more bold and interest generating.

I do not like seeing your forum stats at the top of your forum homepage (for guests at least).

You should try out our Relevant Replacements.

You should modify your templates to place a H1 tag on your thread and sub-forum page titles.

I prefer to eliminate as much non-essential information on your page as possible, particularly for guests.

[How to] Setup Relevant Replacements with vBSEO

Check out Step 5. here:
Briansol's Ultimate Guide to vBSEO

Also check out:
How do I change <h1> formatting in CSS?