Actually the new launcher lets you play any version, just click "Edit profile" (and you can have multiple profiles with multiple versions). I personally keep a 1.5.2 profile for the worlds that I play and a "latest" profile to try out the new stuff.
Wow, the 1.6.2 is the first vanilla I've observed that actually sends the 0xfa "Plugin Message" packet to the server. Need to implement that in the server (I have 1.6.2 support otherwise working

)
1.6.2 supported in rev 1669. I think this was the fastest protocol adoption ever - only a few hours after the version was released

Minecraft 1.6.3 wil be released soon. The pre-release is already released.
1.6.3? I thought they were doing 1.7. Got any changelogs?
They are quickly fixing a bug before they release 1.7 with the new world changes. Structures like witch huts weren't saved so when the world generation is changed stuff like witch farms would not work becouse Minecraft didn't know that there was a witch there initialiy
Changelog
Huh? In the afternoon I was still playing 1.6.2 and now it's 1.6.4 already? And according to the protocol wiki, nothing has been changed, except for the protocol version number? Wtf, Mojang?
Support added. They don't seem to have changed anything.