This is a bad idea. The whole point about big and small version numbers is that you know what to expect. If you develop an app for Windows 2000 (5.0), you expect it to work in Windows XP (5.1); but you expect problems in Vista (6.0). Same with Firefox extensions - if it works in 3.5 then it should work in 3.6, but you can expect trouble with 4.0. Minor version numbers should only contain superficial changes; major versions should make deep changes to the APIs.
Continuous change simply isn't possible; sometimes you need to stop and re-write large parts of the system from scratch.
Reminds me of the time Microsoft bumped the version of Word from 2.0 to 6.0, because people thought it wasn't as good as WordPerfect 6.0.