As lots of the things we planned to do for our Beta (Version 0.6) take longer than expected (surprise ;) ), we decided to not leave you alone without an update for so long.
We will push update 0.5.1 that will include most of the stuff we've prepared fo 0.6 so far during the next week. The patch will include lots of performance optimisations, the new lighting, the new intro, new ground materials, some remade (interactive) objects to play with, 2 new animations, and much more.
For full release notes, see the Release Notes thread in the forums.