On Nikon and Canon systems, the stabilization feature is built into the lenses themselves where "supposedly" it's more effective than the body mounted stabilization systems like on Pentax. The advantage of Pentax is that you have the stabilization on every lens you use, albeit perhaps a bit less effective. On Nikon and Canon you get "claimed" more effective IS/VR on the lenses, but then of course you have to buy the feature for every lens since it's not in the body. I don't think either way is superior, just different.
And yes these are the "kit" lenses. I'm not sure if Nikon is going to be discontinuing their non-VR 18-55 kit lens or not - ditto with Canon. I suspect they might be, but who knows.