Mojang announced on their blog today that Minecraft 1.4.4 had entered pre-release stage. Given that this release occurred just days after the 1.4.3 pre-release, many Minecraft players were surprised by the update.
However, Mojang explained that the 1.4.3 pre-release had some major problems that needed to be fixed, so they decided to just move ahead with releasing a new patch.
The 1.6 update addresses two major complaints about 1.4.3, including:
-Players unable to swim upwards
-Placed torches jumping between walls
Both of these issues were enough to prevent an official release of Minecraft 1.4.3, so 1.4.3 will forever be known as the update that never actually reached the launcher.
Along with fixing those two major issues, 1.6 addresses about twenty new bugs, the full list of which can be found here. Notable bugs include fixing strong water current, tab key functionality on Mac, squids flying through the air, and Iron Golems crashing the player as they walk.
Expect 1.6 to hit the launcher in the middle of next week. Until now, you can install the pre-release copy of 1.6 manually after downloading it from the Mojang.com blog.