From the
apt-get ubuntu_9.04 dept.:
The Ubuntu team is pleased to announce Ubuntu 9.04 Desktop and Server editions and Ubuntu Netbook Remix, continuing Ubuntu's tradition of integrating the latest and greatest open source technologies into a high-quality, easy-to-use Linux distribution.
...Ubuntu 9.04 will be supported for 18 months on both desktops and servers. Users requiring a longer support lifetime may choose to continue using Ubuntu 8.04 LTS rather than upgrading to or installing 9.04.
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