I really like the theme and layout and think it has some great potential. Some points:
- Personally, I am not a fan of websites with a pure black background. It makes my eyes hurt
- The capital letters are great for the header buttons and maybe titles, such as "Latest Activity" but all the other text should be proper case
- The blue on black is really nice
- I love the username and password part at the top right. Really web 2.0 and slick
I would recommend you maybe lighten the background, or if not, at least give your users an option to remove the dark background.