It seems like even if the jb is done, a lot of the usual tweaks will need to be reworked due to some changes Apple made. See this post:
Originally Posted by iphonedyou
"At time of this writing, there is no jailbreak out yet. In addition, none of the new features are worth trading away your jailbreak. The first jailbreaks are likely to be tethered. So make sure you wait for an official update of greenpoison or redsn0w before you update. I’ll definitely announce when these are ready.
In addition, with 4.3 comes apple’s implementation of address space layout randomization (ASLR). In short, this will mess up the way mobile substrate works. You will need a new mobile substrate in order to use your favorite tweaks such as winterboard, sbsettings, bitesms, folder enhancer, etc. So you should definitely avoid 4.3 until an “official” jailbreak is released for it."