Well, I just don't really have a justifiable 'need' to root, as I said above, sure I could root and take advantage of it, to a point. But in my mind, I'm pretty happy mostly stock.
Remember, my S3 is international unbranded, so I've got no bloatware. Only the standard Sammy crap. (all dumped into a sammy folder on the ap draw, as with all the Google junk)
Plus as I don't / won't pay for phone insurance, I don't want to void the warranty just yet. The old portal was pretty much an entry level phone (equivalent to a galaxy ace) so it was cheap, and I just wasn't that bothered about it, but I still didn't root that until after the warranty expired naturally. So having shelled out $450 each for two S3's, and being as awesome as they are, I'm sure I can live with them being stock for a while longer before deciding to 'play around' with 'em.
Atm my only reason for rooting, really, would be to gain control over the CPU and over/under clock via Tasker when charging etc, but the quad 1.4ghz is meaty enough, when throttled to quad 1.0ghz on power saving for doing what I need to be honest.