kieranu

I'd say that empirically the D7000 pips out the OM-D but I got the OM-D w/ Nauticam housing because I wasn't invested in Nikon or Canon (Minolta / Sony) and I liked the compactness of the OM-D for travel combined with the relatively low cost of housings and ports.  And I also shoot video.  Between the insurance on my scratched video port and selling off my Sony / Minolta gear and compact underwater camera gear I'm pretty much even with the port for the kit 12-50mm lens and a single YS-D1 strobe with the Nauticam tray and arm.

http://www.dxomark.c.../(brand2)/Nikon

Also, what is the depth rating for the Ikelite and how deep do you plan to dive with it?  Does the Ikelite give you as much control over the camera as the Nauticam?  I don't know the answer, but these are the questions I would ask given my old Ikelite was rated to 40m (though it worked better than me at 70m).