"Ubuntu 15.04 LTS information with details of advanced features including support for Ubuntu 15.04 which will last for 5 years."
"Doing anything special on April 23 next year? You should be as its the release date of Ubuntu 15.04 Vivid Vervet. The spring launch, along with the dates of various development milestones needed to get there, have been agreed to by the Ubuntu Release Team and on the Ubuntu Devel Mailing List."
"Having covered some 10 Ubuntu release over the past five or so years, I`m familiar release schedules and issuing caveats about always subject to change. While that remains true, I`m yet to see any release differ too wildly from its original schedule."
"Key Ubuntu 15.04 Release Dates with all releases after 13.04, Ubuntu (Unity) only makes fleeting appearances at select milestones through the six month development cycle, taking part in the `final beta`, `release candidate` and `final release` stages only."