I think that's actually why there's not a click-and-it-does-it solution for the G1 - because there's far less restrictions on what apps you can install on the device there's much less incentive for people to 'risk' fiddling with it.

Tethering is probably the 'killer app' for jailbreaking/rooting on both platforms for most people, but there's a lot more to be gained by jailbreaking your iPhone.

Having said that - I haven't bothered to re-jailbreak mine after the last few updates since I realised I never used the jailbroken features.