Yeah, the 2007 "archival" release will bring a LOT of merchendise tie-ins, without a doubt. I know that the 1998 SW encyclopedia was written by Steve Sansweet, so I suspect that he will do the 2007 one, since he's the expert on the Star Wars saga in its entirety. Although Nathan Butler wouldn't be a bad choice either.

What I think would be interesting is if George Lucas himself wrote some sort of book detailing his views of each film and his personal thoughts and experinces on the saga. Man, no matter what opinion you have of him, you've gotta admit that that would be AWESOME!