Interesting idea, probably quite good for stock photography (I'm a bit unsure though). The texturing on the lids really appeals to me. The framing seems a little awkward, but I really enjoy the softness of the glass way back there outside the depth of field.
I'm not sure how this would apply to stock photography too much, but I'll pretend it does anyway. The tight crop is not conducive to this angle IMO. I think the picture would work better from a slightly less direct angle. You could still keep the macro approach to it to some degree and still make it successful I think. I would've cleaned off the tops of them too to free them from stains and such
Nice composition. The lighting is even across the shakers and no large glare or hot spot. The one thing that stands out is that the salt shaker is in focus while the pepper shaker is not. This throws off the symetry of the shot. When working with just two main subjects that are near identical, the eye wants to see them as such. I like the angle and tight crop presented here. One last thing to note, when working with shiny objects, make sure that finger prints and smudges are wiped clean prior to your shoot. Although very small, there is a smudge on the pepper shaker. Again, the eye is looking at this even though you may not realize it while viewing. Nice shot.