I installed what will be Drupal 5.x on my computer last night for the first time and was amazed at how easy it was to set up and get it working out of the box. Drupal 5.x is still in development but it's possible to download the current snapshot and try it out - and it seems like it's not too far from being ready for release.
After downloading the latest version of Drupal to my computer, accessing it through the web browser, it now gives a friendly screen telling you to give the correct permissions on the configuration file instead of giving SQL errors as 4.7 had done. Once I'd set those permissions, I was taken to a configuration screen that asks for database information (which I still had to set up by hand, though in the future this step may also be done for you) and that was it. Click the button and Drupal is ready to go. No more worrying about importing database tables and everything, it's all taken care of by the installer now.
I've not had a proper look around yet but the overhaul of the administration section seems to break things down into much more understandable areas (content, users, site configuration, etc) than the previous flat listing of everything. It may take me a while to find where some things have moved to, but it's a great step forwards in making Drupal more friendly to site administrators.
I'll be starting to upgrade my modules for 5.x soon, though I am planning to continue support for the 4.7 branch for some time still.