Update 1, the first of Autodesk’s Updates (formerly Service Packs) for AutoCAD 2010 is now out for AutoCAD and AutoCAD LT. Equivalent updates for various verticals will follow soon. The Readme contains information about what was fixed, so I won’t reproduce that here.
As always, read the readme first and exercise the usual paranoia. However, my experience of the pre-release versions of this Update has been positive.