The challenge is so strong that he make Geohot back to jailbreak scene. For who don't know,
George Hotz (aka Geohot) is a very talented Hacker, Geohot is also the hacker behind Limera1n and Blackra1n jailbreaks, he also was able to jailbreak PlayStation 3. Now a challenge is being held between p0sixninja -the hacker behind Greenpois0n- to dump iPad 2 (A5) bootrom.
So far, threre's no jailbreak available for iPad 2, but hackers are working hard to handle this. Comex -the hacker behin JailbreakMe- is working now on iPad 2 jailbreak via userland exploit.
What is difference between Bootrom and Userland exploits ?
Bootrom exploit is difficult to discover and develop than userland exploit, as Bootrom exploit is hardware-based exploit so that it can be fixed only with hardware upgrade which means that it will also work with upcoming iPhone 5, so we can conclude that bootrom exploit has long lifetime. Userland exploit is a software-based exploit so it's not time consuming compared with bootrom exploit but, its weakness that it can be easly patched on firmware upgrade.
There's no estimate to arrival for iPad 2 jailbreak so far, but iPad 2 users should be optimistic as we will have more than solution for jailbreaking the lovely iPad 2.