BB3 is already out, so is BB4, if you count the community-driven projects available for download here:
http://lilliput.amiga-projects.net/bbag4.htm
Occasionally people have trouble installing them, but that's the nature of Amiga software in general for ya. Many crazy configs, occasionally someone's going to have an issue. Myself and many others run them daily without any trouble. Runs like butter on my A2000!
There's even updates beyond this, things like Peter K's icon.library that's updated every month or so. Definitely worth a look on Aminet for updates to many of the "core" OS files!
I sort of knew that already, but thought that BB1 & 2 were the only official Boing Bags released and everything after that was unofficial.
My point remains that some users would prefer an updated AmigaOS3.9 CD with all of the latest improvements already included, plus a comprehensive Install Script that would give us choices to install or not install any of the more questionable recent upgrades for AmigaOS3.x, would be really great. Some users out there (maybe you) are much better and more patient at testing and installing dozens of new patches and updated files, to get the most modern and efficient AmigaOS3.x experience, while others (like me) just want to pop a CD into the drive and hit the install button, with the possible exception of making a few simple choices on files that work better in certain situations, or on certain specific hardware models.
It would be a difficult job to find and obtain all of the approvals from 3rd party developers who have contributed to all the parts contained within AmigaOS3.9 and all of the Boing Bags since that time. Some of them may want a small royalty for selling their work again (which is fine with me). I would guess Hyperion would need to be involved, as I believe that they own the rights to AmigaOS3.9 (possibly excluding a few parts of it contributed by those same 3rd party developers), but I think it could be done, if someone had the determination to stick with it and track down everyone that has contributed.
I appreciate the people still working on updating AmigaOS3.x, because I never want to see that part of our community fade away, even though I am also a MorphOS and AmigaOS4.x supporter and user.
Edit: Just thought of another way in which much less approvals would be needed. If the updated AmigaOS3.9 were only an executable file that only contained the required files that have been added or modified after AmigaOS3.9 BB2, then it could include in the installer script, options to specify the locations of the users AmigaOS3.9 CD or ISO file and the two Boing Bag files on his hard drive. Then it would use those resources to do a new install that included the new and updated files that make up the unofficial Boing Bag 3 & 4 contributions. That way no copyright or intellectual property infringement would occur. The only downside to this idea is that those original AmigaOS3.9 CD's will eventually begin to fail or contain read errors.