The iPhone Dev-Team has announced that their 'backup plan' untethered jailbreak is nearly ready and will not require a restore of your device.
According to MuscleNerd, the backup plan for those w/legit access to 4.2b3 IPSW is about ready...again though, better to wait for comex
Thanks to comex, redsn0w can now handle much bigger files than ramdisk 25MB limit. Useful for "backup plan" 4.2 untether
it shouldn't require a restore...just another redsn0w run. (That's the goal!)
Interestingly, comex has also written some code to retrieve files from a damaged iOS filesystem.
This latest @comex code also allows retrieval of photos+files stuck behind an unfixable filesystem problem...good stuff!
Comex is still working on a more extensible untether; however, those with access to the 4.2b3 IPSW will be happy to know they may soon untether their jailbreak.