It’s one of the (not so) well kept secrets in WordPress that a team is busy redesigning the admin interface. In fact, if you use WordPress.com you have likely noticed a change in the admin layout some time ago. For those of you using a self-hosted WordPress site the change most likely won’t happen till at least 3.7.
However, for the early adopters and developers you can preview the new layout by using the MP6 Plugin. I personally (and from the forums, many others) felt that the new sidebar was too dark. It also currently looks like MP6 plugin won’t give users the option to switch between layouts. For this reason I’ve created MP6-light which basically works by adding a stylesheet that makes the admin a bit lighter. Check out the project page or get the plugin from the WordPress repository.
NOTE: This plugin requires the MP6 plugin to be installed.
P.S: I’m also looking for people to get involved with the project on github.