SQL

There are a lot of changes since SP1, so it is worth reading the release notes to make sure there haven't been any incompatible changes made and, of course, it is not recommended to use CTPs in a production environment but if past SQL CTPs have been very stable.

You can grab the new binaries here.

The changelog for SQL 2005 SP2, so far, is here.

.NET 3.0 RTM'd too today - it is the week of releases at Microsoft it seems.