--Jason DeStafano wrote---
I'm thinking about releasing some software I've written
and using the GPL. My question is if I release it under the
GPL and say 6 months down the road I've made some
new enhancements and a company wants to buy the software
from me. Can I (as the author) stop using the GPL on a new
release and thus sell it to someone an intellectual property
(and thus discontinue making updates). In other words, does
the GPL forever premit even myself from selling my own
GPL'ed software?
---
   First, the usual IANAL disclaimer. However, this discussion seems to
come up a lot, and general concensus is as follows:
   Let's say that you release software FooBar v1.0 under the GPL. Then
along comes BigSoftware that wants to add some features to it. As the
developer, you can change the license of future derivations, so you
decide that Foobar v2.0 (Foobar v1.0 + new features) will be
proprietary. That's legit. *HOWEVER*, FooBar 1.0 is still GPL and cannot
be changed. Thus, someone is free to come along and take the source for 
v1.0, add the same functionality that was included in v2.0, and release
the new code as FreeFoo under the GPL.
   If I am not mistaken, this is what happened with ssh. The author
originally licensed it under the GPL, but then licensed future versions
as proprietary. Along came another programmer, took the existing GPL'd
code and added the same functionality, and thus OpenSSH was born.
   Same story with the CDDB database. It was originally open, but then
someone got greedy, decided to form a company (Gracenote) around it, and
closed it off. People were more than a little ticked that something that
they had developed (submitting music info) was now closed, took the last
open information and formed FreeDB.
   Note that there is nothing about the GPL that forbids you from
selling GPL'd software. RMS used to sell Emacs for $150, I think. It's
just a little harder.
   Someone correct me if I am wrong.
   :Peter