I wound up getting a x86. Wanted the mac, and will get one some day, but I needed the box for work and didn't want to take a chance on the mac not being a good choice for java/web services development. I also read that the mini mac has a striped down version of OSX and I that is what did it for me. I would have needed a full blown Unix OS as fall back if KVM hardware did not work or was too costly.
Mac is a great platform for your javascript, and for web development, particularly if you like forefox! ... IMO, your decision was lacking proper input!
The OS on the box is the same on my G5 desktop...
The mini is a G4, so why don't you look on eBay, or somewhere and buy a used one for a couple of hundred... then plug and play!