Ubuntu team is already planning for 10.04 LTS, which will see the light of day in April 2010
Ubuntu 10.04 (codename Lucid Lynx) LTS will be released on April 29th.
Ubuntu 10.04 Release schedule
December 10th, 2009 – Alpha 1 release
January 14th, 2010 – Alpha 2 release
February 25th, 2010 – Alpha 3 release
March 18th, 2010 – Beta1 release
April 8th, 2010 – Beta2 release
April 22nd, 2010 – Release Candidate
April 29th, 2010 – Final release of Ubuntu 10.04 LTS
source: http://www.ubuntugeek.com/ubuntu-10-04lucid-lynx-release-schedule.html
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