I was having a ridiculously annoying time trying to get beta 7 working on my phone. Here's a description of the problem. Others might not have the same exact problem, but anyway: I was on iOS 4.3.3 (jailbroken of course) and Beta 7 would install just fine. The problem arose when I ran RedSn0w. After running it, I would get stuck at the recovery/Connect to iTunes screen. Nothing I could do would work. I uninstalled every piece of Apple software, removed every file related and redownloaded everything. Still didn't work. Tried a bunch of other things, and through the help and involvement of Kiba and AppleHacker from Sinful iPhone, we eventually found that the only way to get it is: Have Beta 6 working on the phone, then do a full Shift+click restore of the beta 7 .ipsw (or .dmg if you're on teh Macz). Do NOT have your phone in DFU mode. Just restore it and it'll install fine. Run Redsn0w as your normally would and BOOM! Your phone explodes. No, just kidding. It'll work! If you're not a Dev (like me) go ahead and remove the beta strings through iFunBox, reboot w/ RedSn0w and enjoy!