GPL - any version of GPL GPL2 - only version 2 GPL2+ - version 2 or later GPL3 - version 3 only GPL3+ - version 3 or later
These are all substantively different (except the last two.. for now) so how do we express these? Should we actually create common licenses GPL2+ and GPL3+ which reference the other two, and make GPL reference them all? Do we need a GPL1 and GPL1+?
- P

