First of all, thanks to the developers for providing this software in this fashion. I was about to go teach myself (try) how to compile Apache with mod_perl when I came across this. This is a great idea.
Please note that I haven't yet installed this as I have a couple questions so far:
1. What version of OSX compatible with? I notice XAMPP hasn't been updated in a while but OS X is now up to 10.4.4.
2. Has anyone performed an Apple's software update after installing this and, if so, did it keep working? I don't care if I simply have to update some config files. I do not want to become excessively dependent on the developer to release major fixes though, as it appears XAMPP for Mac hasn't been updated in 6 months according to the download page (which states Aug 15, 2005 as I write this). If I recall correctly OS X 10.4 has been updated at least twice since then. If the lack of updates is because they aren't necessary that's great (I just have no way of knowing as documentation seems very limited).
Other than that, as I said, fantastic idea, this could open up possibilities for a lot of developers that aren't otherwise sys admins.