Hey, we thought the Bootloader check from Oct 2009 iPhone 3GS and later would stop us, but the crackers broke it. Took a while with each release but the untethered JB for later devices was always there. I'm sure the iPad 2 will reach that state soon where they regularly crank out a untethered JB also.
The benefit of iPhone hacking is that you have one GIANT community going at it. With Android, you have talent scattered all over. Some of the devs for some phones are just flat out geniuses, but you wish they could also dedicate some of that effort to other devices. For example, the Motorola Milestone hacking has been insane. We got so much to work on it. Thank goodness so much was shared with other communities like Dx development for the 2nd init that finally is working. I'm pretty sure the Milestone guys helped a ton. But at the same time, a lot of that development is useless for say the guys at HTC cracking the Incredible S. I've seen both sides and while the Milestone crew is still more talented, the IS development team has talent. It's just a shame all that talent needs to be spread thin.