#6 - April 22, 2011, 1:10 a.m.
Never say never, but developing for and supporting multiple codebases (while possible) would very unlikely be worth it. It's really not as simple as people make it out to be. Those playing on a 'classic' server would still require support, and absolutely still request bug fixes, changes, additions, content, etc.
The notion that the game frozen in time with no patches, no new content, no changes, would be fun to play forever, is in my opinion a very clouded vision of how it would actually play out.