Being released along side Ubuntu 10.04 LTS Beta 2 proper is similar updates to Kubuntu, Edubuntu, Xubuntu, and the various other Ubuntu flavors like Ubuntu Server and Ubuntu Server for UEC/EC2 cloud computing platforms.
Ubuntu 10.04 LTS (codenamed the "Lucid Lynx") is set to deliver a few performance changes, new kernel flavors, a faster boot experience, a new theme, the introduction of the Ubuntu One Music Store, a new interface for Ubuntu ARM Netbooks, integration of Plymouth, and many other changes.
There are also many package updates found within the Ubuntu Lucid repository like GNOME 2.30, KDE Software Compilation 4.4.2, Xfce 4.6.1, OpenOffice.org 3.2.0, GCC 4.4.3, the Linux 2.6.32 kernel (with 2.6.33 DRM back-ports), and X.Org Server 1.7.5.
The release announcement for Ubuntu 10.04 LTS Beta 2 can be read on the Ubuntu announcement list. The final release of this Canonical Long-Term Support release is expected on the 29th of April.
Succeeding Ubuntu 10.04 LTS will be Ubuntu 10.10, which has been codenamed the Maverick Meerkat. The expected features for Ubuntu 10.10 six months down the road (on 28 October) is integration of X Server 1.9, GCC 4.5, and GNOME 3.0.