Certainly an interesting piece of software.
Reading deeper about it, it appears to be simply an OS X port of the popular open source command line tool, Imagemagick. GD and Imagemagick are the main graphics tools used on webservers for programs such as G2, Copermine etc etc etc and by the image gallery of this website.
The list of files supported is exactly the same as Imagemagick including DNG. They have leveraged Apple's Core Image to carry out some additional functions.
While Imagemagick does not offer full raw support, if dcraw is installed with it, it can delegate to dcraw and treat it as a module. I am certain the Pixelmator guys will add bundle dcraw with the app at some stage and probably have only decided to go one step at a time.
I am certainly signing up as I only use Elements for resizing and a few other steps so this + Capture NX will suit me fine. The low price is also very appealing especially since I just could bring myself to buy the full version of photoshop which I consider to be a bloated tool really designed for graphics artists.
