> For what it is worth, I'm happy that they've done this work and I
> expect to make use of it in the future....
> And yes, both in the old way and the new way we would retain the
> ability to give or sell proprietary licences
Since, as I understand it, Tahoe-LAFS is designed to be used in hosted environments, the practical difference between BSD and GPLv2 is pretty small. Why not just license the system under the 2-clause BSD license, and forget about copyright assignment? The BSD license allows you to sell all the proprietary add-ons you want.
Personally I don't have a problem with most of the OSS licenses out there. But if I contribute code under a certain license, I would like it to stay under that license, and not morph into something else. It's only fair.