Microsoft, I'm looking at you: Windows Vista is version 6.0, Windows 7 is version 6.1 and Windows 8 is version 6.2
When they updated Vista to 6.0, a bunch of programs people had written for Windows broke. They checked for "majorVersion == 5" and if it wasn't 5, they would say "We don't support this operating system" and quit.
This is one (of the many) things that hurt Vista sales. Application backwards compatibility is a big deal to Windows.
That's why they started using 6.x from then on. If the changes Microsoft makes to Windows are backwards-compatible, there's no reason to require every software company to update the version that their software checks.
this is a website, it's not like we can choose to downgrade to a previous version or anything... Let's be practical: when do you ever refer to a WL version number?
For the most part, you're right. But there are some circumstances where it matters. If you open the game before the update and never refresh your browser, your client will actually be using an older version than the server.
It's much more important with the Android client, which doesn't auto-update yet. I still see people using versions that are months old since they're lazy and don't like updating :)
