Edit: The advantage to rapid releases is that you can roll out minor updates when they're ready without having to wait for big ones, and you don't have to rush big ones for a deadline. If you miss one release, it's no a big deal because there's another one coming right up. Release when it's ready!
The Linux kernel is on version 3.15, for example.
> In principle [...] the major number is increased when there are significant jumps in functionality such as changing the framework which could cause incompatibility with interfacing systems, the minor number is incremented when only minor features or significant fixes have been added, and the revision number is incremented when minor bugs are fixed.
As did Java. Java 1.4 was released in 2002, and the next version was Java 5 in 2006.