Ubuntu 11.10, scheduled for release in October 2011, will be code named Oneiric Ocelot. This will be the hardest to pronounce out of any of the Ubuntu code names. In fact I still can’t pronounce it! But that doesn’t really matter so much as it is just a developer code name and most people will refer to it as Ubuntu 11.10.
I will post when more information on 11.10 is available.