There is a tradition in Ubuntu community that Mark Shuttleworth will nickname the upcoming release. Remember that Ubuntu releases come out every 6 months and the numbers are YEAR.MONTH of the release.

Ubuntu 10.04 was Lucid Lynx , released in April 2010 Ubuntu 10.10 was Maverick Meerkat , released in October 2010 Ubuntu 11.04 is Natty Narwhal, will be released April, 2011 Ubuntu 11.10 will be Oneiric Ocelot, will be released October, 2011

We tend to refer to the releases by number (the 10.10 release) or nickname (the Lucid release, the Natty release). Helps distinguish between various versions.

See Mark's blog post: http://www.markshuttleworth.com/archives/646

No, it's called Ubuntu 10.10 - "Oneiric" is just a code name for developers.

And people here downvote when you complain about it...