What is new in Ubuntu 11.04 (Natty Narwhal) Server
For PC users, Ubuntu 11.04 supports laptops, desktops and netbooks with a unified look and feel based on a new desktop shell called "Unity". This version supersedes Ubuntu Netbook Edition for all PC netbooks.
New Features
cobbler and mcollective have been included, which will make provisioning servers easier.
PowerNap 2.0 uses a new method to reduce power consumption and can now monitor user activity (Console, Mouse, Keyboard), system activity (load, processors, process IO), and network activity (wake-on-lan, udp ports tcp ports)
Default dhcpd server updated from dhcp3 to isc-dhcp (version 4).
Eucalyptus is now the latest stable point release (2.0.2) with security and efficiency fixes.
OpenStack (nova) in Universe is a technology preview, with a recent snapshot of 2011.2 (Cactus) release.
Cloud images
Ubuntu Server is available for for UEC and EC2.
cloud-init has been updated to 0.60. This version includes support for resizing of the root file system at first boot, adds minimal OVF transport (iso) support and allow setting of hostname when first booting. Rightscale support has been added to cloud-config and cloud-init.
Cloud images now have support for being run as an LXC guest.
Some of the supporting technologies that have been packaged and included are, Cassandra 0.7.0, ZeroMQ, Membase, and XtraBackup.
Images are verified to run against OpenStack (nova) cloud.