Apple seems to have found a temporary solution to thwart attempts at pwning the iPhone. iTunes is Apple’s greatest ally and it is through iTunes that Apple has found a way to put a halt at attempts to pwn any iPhone for the time being.
Since all the currently available pwning tools require the user to load the pwned firmware throughout iTunes, Apple has decided to enable iTunes 8 to detect and block such firmware from being loaded into the program. Since users can no longer install pwned firmware to their iPhone using iTunes, that puts an end to pwning for the here and now. However, while the DevTeam tries to find a more permanent solution to address Apple's defensive move, they have this to say about iTunes:
The nice thing about iTunes decisions is that we can provide you with patches to counter them. We have one such patch already for Mac iTunes 8 for iPod touch. We’ll be working out the full suite of patches for all the combinations over the next week.
Yeah, we all know they can do it, but the question is; is it still worth it? The whole process of pwning a firmware and loading it to an iPhone is, to say the least, very tedious. And, since there are already a bunch of entertaining, useful and free apps available via the App Store, is jailbreaking still necessary?
[source]