
I have updated the site to use the latest version of Drupal version 5.0, directly from the CVS HEAD.
The update process was fairly painless, except I didn't fully backup the database beforehand and the first attempt failed, leaving both Drupal 4.7.4 and 5.0 unusable. Fortunately I had a nightly backup to restore from, and the second attempt went much better. The only other issue was that my selected theme wasn't available in 5.0, so when I loaded up the new site, it looked completely messed up - no menus or other blocks. Other than freaking me out for a few moments, that was easily fixed.
Most of the (few) modules I was using in 4.7 are either already on the Drupal Modules page or were already updated in CVS
So all in all, it is nice to be at 5.0. The new administration menu system is much nicer than in 4.7, otherwise, I haven't noticed a huge difference so far.