possibly a bad idea
"The code uses a known vulnerability with firmware 1.1.1, which it subsequently patches."
so if it fixes the vulnerability, then how would you go about reversing the changes if you no longer wish to use the not-really-all-that-amazing-3rd-party-apps afterwards? and when Apple release 1.1.x with the killer must-have enhancement that you want, how do you go about applying a hack to revert your iPhone to pre-hack status? surely only a hardware reset which'll wipe all your data
also, while you have to respect there is some technical complexity probably involved in opening the machines via a web interface, it just makes it too easy doesn't it? which means that Apple will be bound to step in to fix it, which ultimately means it'll make it harder for the machines to be hacked in the future
(my main gripe here is that by the time i get my hands on an iPhone at the UK launch next month, it'll be impossible for me to load 3rd party apps and it'll all be the fault of this AppSnap!! damn their eyes!!)