It's okay but a little too simple. Times new roman is a Huge no-no on webpages, it's just so damn dull. Change the font to arial or verdana.
The simple colour scheme works well enough, but perhaps adding a little colour wouldn't hurt? Solid white is very 1999, even just a faint colour as the background would probably help make your site that little bit more interesting.
The flow of the site isn't very intuitive, especially with the sign up link being so small and in a really unusual spot. Make it a bigger and much more prevalent on the home page (if the user isn't logged in already!)