Hey bab why do you advise to hold off till IOS 5?
because it's not necessary to upgrade to 4.3.4 or 4.2.9 since it's only a jailbreak hole patching in that iOS. It's fully working though, and using it give no difference, nothing new, still the same exact thing you have on iOS 4.3.3 or 4.2.8.
If you need an unlock or you like to have your phone jailbreaked then you will do better by staying away from it. You can jailbreak 4.3.4 but it will be a tether one which I believe no jailbreaked wish to have including me. iOS is for soon, few more weeks and you will have hands on it, and that's why I was advising to stay away from the recent release iOS. Whatever I'm saying, it's all your call though; you do how it please you to do with your iDevices