
Banelings can detonate while being burrowed, the Galaxy editor will not be released at launch of the beta, but later and The Jace Hall Show finally featured the StarCraft 2 team.
Short interview with Browder
Sydarm at StarCraft.incgamers.com spoke with Dustin Browder on the evening of Saturday the 13th, the lead designer of StarCraft 2 being mysterious as always, Dustin Browder hints on some surprises:

Yea, I am taking a short break to talk with the fans. I will be going back to work shortly.
You working a lot of hours due to beta crunch time?
Yea, hopefully I can take a few hours off tomorrow.
Beta this week?
Nobody really knows. It depends a lot on testing and how things go. QA is beating on the game as hard as they can. When we get a good build, it will go out.
Ah, so Battle.NET is ready, just waiting on a good solid build?
Battle.NET is part of the build :)
Care to comment on what the "rested points" are on the Battle.NET screenshots from the preview? Does it mean winning games can earn you a higher rank quicker?
No. Wait and see :)
Banelings can detonate while burrowed

Expect a biological minefield when playing against zerg, Blizzard has announced that Banelings can detonate while being burrowed.
Players now have the option to detonate burrowed banelings in the latest StarCraft II builds, so expect to traverse the occasional biological minefield against zerg!
Jace Hall Show featuring the StarCraft 2 team
The Jace Hall Show's third episode of the season has been released, and the StarCraft 2 team is finally featured. Having a few beers, Dustin Browder, Chris Sigaty and company shares their ways of balancing the game.
The Galaxy Editor - user friendly
Karune cleared up that the Galaxy editor will be released during the beta, but not at launch. The editor will feature the same tools that the Blizzard developers uses.
Be aware of fake beta keys
With the beta just around the corner more and more sites are putting up fake beta keys, do not be tempted, only an official mail will gain you a beta key.
Links
Starcraft.incgamers.com - Dustin Browder interview