Dont really look similar except for the background ...
Well in a way that is good news. I was worried there was nothing creative. Though if it doesn't look similar, then perhaps it is a standalone theme after all.
It is possible to make a matching theme to the wordpress blog, but you have a way to go. You need to make sure the header ,the footer and the container styles on the two pages match, as well as the font and the font colours and size.
Thanks for the suggestions Leefish! I am not sure if I will tweak the forum theme or not - but those are great suggestions.