Could those with the book already in their hands, share some tidbits to make the wait a bit more interesting for the rest of us ? For instance, are there any chapter specific alternative advances like the chaplain from the official preview ? Which chapters besides Imperial Fists are included ?

People are making comments about this here: http://www.fantasyflightgames.com/edge_foros_discusion.asp?efid=179&efcid=3&efidt=434911

I can't comment personally yet since I don't have my copy, and it seems several things have changed since the last playtest document.