Pre-ordering will grant you instant access to early alpha builds, which will be updated as new content is added. The current version includes 1 of 5 chapters and is available for PC and Mac (Linux coming soon).
It's currently 50% off and this price will creep up as more chapters are added, so get your pre-order in ASAP!
There is also a brank spanking new website and a new video to coincide with this occasion:
This game looks fantastic!
stunning
Visually very impressive, reminds me of limbo but with a really nice use of colour and depth.