I personally find larger version numbers a bit odd. Generally people tend to work better with smaller numbers. I think the Ubuntu system is pretty good, use the major version for the year and have the month as the minor version. The Chrome 2 month releases could go 1.1, 1.3, 1.5, etc. That way they wouldn't chew through so many numbers. Ultimately I guess projects must go through a reset of their versions before they get to really ridiculous numbers.