Was reading an interview with Jeremy Allison (the maintainer for Samba), and saw something interesting.
http://www.linuxworld.com/news/2007/071707-interview-allison.html
Apparently the new GPLv3 is compatible with the Apache license. This is a good thing, since one could assert that generally it was not the intent of the Apache group to be incompatible with the GPL.
As a result though, I got to reading the GPLv3 for the first time. I especially like section 12:
12. No Surrender of Others' Freedom.
If conditions are imposed on you (whether by court order, agreement or otherwise) that contradict the conditions of this License, they do not excuse you from the conditions of this License. If you cannot convey a covered work so as to satisfy simultaneously your obligations under this License and any other pertinent obligations, then as a consequence you may not convey it at all. For example, if you agree to terms that obligate you to collect a royalty for further conveying from those to whom you convey the Program, the only way you could satisfy both those terms and this License would be to refrain entirely from conveying the Program.
This solidifies something that was only inferred in GPLv2. If you can't legally comply with some term of the license, the entire license is void - therefore you fall back on copyright law and have no right whatsoever to redistribute. Companies can't cherry pick sections and say they don't apply to them, then turn around and distribute the GPL software anyway.