Guys, that's "just" a 6.0L GM truck engine marinized by Crusader. I think you can still find stuff on GM Powertrain's marine website.
In the truck world it's an LQ4 or LQ9 depending on which pistons it got. LQ4 got your standard 9.x comp ratio, LQ9 got 10.0 pistons. And yeah, the aussies have been all over marinizing the LS-x for years now; somebody down there makes decent stainless exhausts WITH O2 sensor bungs.
I think they share the same bellhousing bolt pattern as the "original" GM smallblock, but with aluminum heads and composite intake they've got to be lighter. Plus there's tons of off the shelf custom tuning software if you use the land-based ECU.
I'm just guessing here, but my $1 bet is the LS-7, 427ci small block will be the basis for what replaces big blocks in the future. Imagine the fuel savings with Displacement on Demand during all your idle/no wake zones.