I think DF originally planned to release this before the first issue of the new series. It has a sequence from the first issue in an earlier version that it will appear in Alchemy #1.
Since the time I sent those pages to DF, earlier this year, I have went back, and changed the order of the pages, changed the text, dropped pages, added pages, and redrew or re-arranged many pages.
So actually that preview book from DF can give you a behind the scenes insight into the evolution of the way I re-edit and re-arrange, and fine tune my work as a story.
It will have stuff that I ended up cutting from Alchemy #1, and will have other pages that (at the time) I thought were finished, but that I continued to re-work and add to.
Hope that helps answer some questions of people asking about it earlier.
It also has a very thorough interview about the move to Marvel ICON and the ALCHEMY story.
And some other stuff too, but I can't remember exactly what, as I sent it to DF some time ago.