The first maintenance release Ubuntu 10.04.1 LTS (Long Term Support) has been released by Ubuntu team. It's now still finding it's way to mirrors around the world so no public announcement yet, but if your local mirrors has catch up with this update, you are quite lucky
This release has fixed several problem found on the original release of Lucid Lynx and most problematic packages has been replaced with the fixed one. This should be the recommended version for people who wanted to run a stable version of Ubuntu. If you have used synaptic or apt-get to upgrade your local packages, you won't need to install anything as your upgrade has included all the fixes included in this release.