It will handle it; I have used the Nikon D40 (same place in the lineup as today's D3000, the smallest, lowest-price d-slr) with the 70-200 VR as well as the 7-pound 200mm f/2 AF-S V-G, which is a very heavy lens...no problems were experienced...it's not like the thing is going to fall apart on you...I've shot the D70 with the 300/2.8, another 7-pound lens, and what was at the time, one of the lowest-end Nikon bodies...
As you move up into the bigger lenses, you realize that the LENS is what you end up supporting with your left hand, most of the time, and the lens is where the monopod or tripod screw is fastened, so the majority of the weight is supported at the heavier end of the equation--the lens end. So, it really ends up this way: the LENS is what is supporting the weight of the camera, and not the other way around. Your fears and worries are completely misguided by unfamiliarity with the way heavier, pro-level equipment is actually held and shot, which is understandable.
It's not as if conscious effort is required; when you pick up a heavy lens/camera combo, your left hand (or monopod or tripod) will naturally bear the majority of the weight...because, well, because that's the way it is easiest to do...it's almost like breathing--you do not have to think about it to do it...