Like so many others - A great idea is born, but after months and months of 'progress reports', that idea eventually disappears into thin air. In my opinion, a lot of these theme-projects start out as something awesome in a Photoshop mockup, but when it comes to actually making the layout/theme, they probably run into too many problems while trying to code it and eventually give up or forget about it. Then again, who knows - maybe it was 100% finished and just never released officially?