Having just spent the better part of a day setting up Django on a Centos 5.5 machine I am doing a happy dance at this news. The amount of work to get things up and running is truly painful. Especially if you are on a x64 system.
A completely reworked security framework; among other major changes. We've had a RHEL 6 installation for a few months and are still working thru the changes. Basic Linode users might want to wait unless you really need the Python updates.