You can download and test Ubuntu Oneiric Ocelot Beta 1. As with Betas, it might be unstable, riddled with bugs, and may even crash your system. If you are willing to test Ubuntu 11.10, then who am I to stop you? 11.10 appears to have many few features, such as a new alt+tab switcher, Gnome is no longer included as a fallback option for computers that cannot run Unity. Instead, Unity 2D is now the fallback option. The Unity interface has gotten an overhaul, the dash is transparent, there’s some folder launchers on the bottom. LightDM is now the display manager.
For tons of information not covered here, you can check out Ubuntu’s Wiki: