I've been following the development of Moodle 2 for a long time and one of the major changes in architecture has been the backup / restore system. Recently I've hauled my college (Earlham) over from version 1.9 to 2.4 and am doing lots of course backups on 1.9 & restores on 2.4. I have to say that my experience with the backup/restore system on 2.4 is overwhelmingly positive and I want to give several zillion kudos points to the unsung developers who have worked on this system. I was used to the course backup on 1.9 which was acknowledged to be flakey -- you had to cross fingers and hope that it would backup successfully or restore successfully. Now in 2.4 the system seems rock solid and flexible enough to do some really useful manipulations with user accounts etc. I can't thank the developers enough -- you've made a moodle system manager a very happy camper .
Thanks for your kind words, Mark, which I agree with. It really is a remarkable system when you consider the immense complexity it copes with.
The person who deserves most of the credit is the inimitable Eloy Lafuente (stronk7), who is not only an excellent human being, but did the core re-design and most of the coding of Backups in Moodle 2.x over a period of many many months in 2009: http://docs.moodle.org/dev/Backup_2.0_overview
He also wrote the very first version of Backup in Moodle 1.1 in 2003.