I picked this book up last night after looking at it for an hour in the store.  It looks like it's high quality, my only initial negative comment is one that Palliser has already pointed out: it doesn't deal with 2.Nf3.  That means no Rossilimo, no Moscow, no pure KIA, etc.  

As a big personal positive, this book more closely follows my personal repertoire than Rogozenko's (and Gallagher's) book did.  What that means for everyone else is that you'll get some analysis of different lines here: 1.e4 c5 2.Nc3 e6 3.f4 Nc6 4.Nf3 d5 5.Bb5 Nge7, 1.e4 c5 2.c3 d5, and the Closed Sicilian with ...Nf6 (instead of ...Nge7).  

My first impression is that it's an excellent book.

You're probably right. I play more games on ICC and have thus more statistics. Also, I play different openings OTB and on ICC. The OTB dutch, alekhine and 1.c4/g3 are already somewhat offbeat.

It is surprising to hear that Nf3/Bb5 is not included. Of course, there is the recent Bb5 book which has many suggestions for black. After seeing "Bashing The Sicilian" and reading the Bb5 parts of Kaufman's "Chess Advantage" I was optimistic for white's chances. After reading (parts of) Palliser's Bb5 book, I now feel that these positions offer white very little.

Now there will not be much on Nf3 lines, meaning that this probably will complement the Safest and Sharpest Sicilians books from Chess Stars well.

It's a rather interesting phenomenon at ICC. When I drop in rating (and thus play lower rated players) I meet main lines much less. It's anti sic and d-pawn specials all the time. When having a high rating I mostly meet main lines.

No Rossolimo or Moscow?  That's too bad.  Most Open Sicilian books don't cover the Rossolimo or Moscow either, so most people expect to buy one open Sicilian book and one anti Sicilian book to cover their repertoire.  I play 2...e6, though, so these lines aren't a problem for me .

Alumbrado - many thanks for correcting this thread's title!
Slates - I guess it'll be out over here in 3-4 weeks as it's got to cross the Atlantic after publication, but depending on the printers and distribution it might be somewhat quicker than that. Comparing it with P1d4, it must be said that the format's better! In short the book only covers all those annoying non-2 Nf3 systems, although clearly there are some transpositions and crossovers: i.e. 1 e4 c5 2 Nf3 e6 3 c3 d5 4 e5 gets a mention, but there's no Rossolimo or Moscow coverage.

Is the book already out? Everyman mentions it is only coming soon.

Alas this is not true anymore. There are several variations, in which the typical setup Qe2, Bf4, Rfd1, Rac1 is insufficient: the Dragon, the 6...a6 variation, all the ...Nge7 variations, the early queenside expansion.
I am not rated higher. Still it is my impression that studying the Morra Gambit takes more time these days than most Open Sicilians (eg a repertoire based on 6.g3 or 6.Be2).