Just wanted to give an update: I moved one of my projects with about 10 modules over to the new import method, and so far it's working perfectly. I should also mention that the new method has greatly simplified the way I write modules. I used to have a z_import_modules.py model that should run all of the local_import() calls, then instantiate all of the objects in those modules. Now, my modules are more like regular Python modules, which I import at the top of the controllers that need them. This is very nice!
I do have a few suggestions though, now that I've got some experience with using this new method: Jonathan actually mentioned having a current.application Storage that would store things like auth and db that are created in models. I would REALLY like to see this. I still need to have my z_import_modules.py in order to to set these things manually to current. I understand that it's easy enough to set these yourself at the end of db.py, but having a standardized Storage object with these variables would be better in the long run. My only other thing is: How much effort would it take to get the Storage class to be imported when you call "from gluon import *"?