Just a note, if you are still only seeing ver 2.4.0 showing as available, try changing the update settings from stable to development to next version etc, saving each time and then checking again for available upgrades. Don't install anything yet, just check. I had to cycle through a couple of times, then 2.4.1 finally popped up as being available on the stable release. Also, when it does finally show up, don't just upgrade from the upgrade page, go back to the home screen, wait for the check again, and then take the link. If you try to upgrade from the upgrade settings page after it first finds it, if fails for some odd reason, well it did for me. The upgrade took all of 2 mins and was painless, so far so good!
Also, before you do the upgrade, I suggest taking a backup and if you have it virtualised, also take a snapshot...might save those skid marks if it happens to go pear shaped on you
Anyway, I hope that helps someone