Today (May 4, 2013) I will begin the process of backporting R 3.0.0 to Quantal, Precise, and Lucid. This will include all the recommended packages and the packages for R found in the universe repository for Ubuntu. Things to keep in mind:
If you do not want to receive these upgrades and you use the CRAN repositories or my Launchpad PPA, please remove them from your apt/synaptic sources lists. This will keep you on your current versions.
You could pin the old versions (search google for “apt pinning”), but since updates will only be coming for R 3.0.0, it is easier to just remove the repositories.
This should be complete by Monday, but it may take longer depending on server load.