Actually, we and bzr are both good.
Those "subrevisions" are there, and all your independent changes are still listed individually.
The problem is that the web interface that Launchpad is running does not show the subrevisions on a "main" trunk. It only shows the last shared revision of two branches, and then the revision at which those two branches recombine.
I think this link finally shows the details that are now suppressed on the main view:
There are a few bugs recorded against Launchpad in regards to this. I sent Ted a list. I think they *really* need to bump up priority on those.