As I understand it A, JBing is not & can not damage your phone.
The worst you can do is lose youre settings &/or personal information but if you are wise, you will backup everything & use Tiny Umbrella before you JB.
I personally have not used it & I am dying too, but it started out very buggy as you can probably tell by all the post here since last night. And since Im going out of town on business tomorrow I just didnt have time to work thru' the bugs & potentially have a non-working phone on my trip.
But as soon as I get back Ill be all over it.
Some of us think one thing or another about this or that developer & all thats just drama & excitement that will be over soon.
Dont let it stop you from JBing your phone. Itll all work out & youll have a great experience.. Good Luck!