Possible Apple’s commercial errors that lead to such a high rate of iPad hack:
1. Initial international appstore release, not only U.S., would have made possible for outside U.S. customers to actually use the device (having full apps content available) as it was, instead of being forced to go for Installous.
2. iPad apps price set lower from the beginning, instead of 2-10 times higher than iPhone’s; that discouraged a lot of people and made everybody either wait for price decrease or go for Installous
If iPhone could be hacked / unlocked for usage purposes (being originally operator locked), iPad has to be hacked for pirate content reasons exclusively.
iPhone 4 will offer some of the most popular Cydia features: multitasking, background apps, folders and so on (actually, most of those apps were rejected by Apple for being a competition to Apple’s own implementation plans). I’m curious to see iPhone 4 hack rate, but not too curious. Without a stronger encryption and maybe cloud architecture I can only expect a higher hack rate than in iPhone 3G / 3GS.