I am really liking this alot. The color usage is great, the pattern background on both the header and welcome message is a very nice touch.
I like using pattern/textures on forums in this way as long as they are tastefully used. You hit the mark there.
Your logo is different. In this case, different being a good thing. I will suggest tho that you make some space above the logo, and between the bottom of the logo and navbar.
Otherwise it looks squished in there.
The postbit is nicely done. The only thing I do not like, and it seems to be inherent in XF when you use the extra info, is that large blank space beneath the content. I really hope that they remedy that in future versions.
It's too bad that the blackish parts of your logo isn't the same color as the border around the top part of the navbar.
Then you could sit your logo right on the navbar and it would look like it's all one piece.