The header area needs work, I don't like how the header is placed behind your layout. I would move it up, and then add in the logo of your blog over it.
I suggest you move the menu on one of the sidebars and leave the header as it is. maybe add some text or logo to it. The rest of the design is a bit plain.
There is no logo on the page...Name your site so that people know what it is about. Add more featured sites