What terrifies me about the GPL is that some segments seem to imply if read the right way (accoridng to the copy in my old Suse 6.4 manual):
-Modified files must be identified as such and marked with date of modification-- it sounds like the spirit of this text is "You've gotta keep a change index file"
-If I distribute the binary commercially, I can't use the "I got the source from foo, and you can too" escape route. This means I'm sunk with storage requirements for a package that nobody may want if, for example, I'm just offering CDs with Windows gimp and openoffice, in case someone demands the source.
I'd also prefer a stricter definition of what will invoke the need to GPL a resultant work, since "derivative work" is a very subject to interpretation. Just say "nine lines safe, ten lines not." It probably also differs by region; probably there are countries where some GPL-forced programme can be safely non-GPL.
Of course, I think the only real answer is to completely wipe out copyright.