There are six new block types (five of them have unique abilities), one new monster, a new dimension, and a couple of bug fixes. Once I get the portals working, I'll have something very interesting going and I'll spend the rest of the time leading up to the release adding new smaller features and polishing stuff.
Notch later explained on Twitter that "you will eventually be able to link servers with portals," though the timing of that feature is an emphasized "NOT SOON."
Persson's company Mojang Specifications has found an office and has grown to six employees with three programmers, a pixel artist, CEO, and a business developer.
Minecraft.net has also been coming under some Distributed Denial of Service (DDoS) attacks. Kotaku has dug up a 4chan post claiming to take responsibility for the attacks, but the authenticity is uncertain. According to the post, the attacks are happening because gamers want more frequent updates from Notch.