But, on receiving it, I find the packaging doesn't mention the D90, although it does mention many other models, and it doesn't fit my camera. I'm wondering if I should be looking for an adapter for it, or if I should return it and find something else.
I'm interested in pursuing night photography and want the remote to cut down on any vibration when I'm releasing the shutter.
If the item you bought matches the packaging shown on Amazon, the furthest adapter is the one you will use for the D90. It plugs into the GPS port (bottom port on left, under its own door.) Observe the groove, this is often a very tight fit and may give the impression of being wrong at first.
Check the adaptor plugs that came with the remote. One is the 10 pin Motor Terminal Release plug for D_ and D_00 series bodies. One should fit the Accessory Terminal (the bottom terminal on the side of your D90 under the rubber door (#14 on page 4 of the D90 Users Manual)) on your D90. That is where the Nikon MC-DC2 Remote Cord plugs into the D90.
>I'm interested in pursuing night photography and want the >remote to cut down on any vibration when I'm releasing the >shutter.
For all but subjects in motion you may find the timer function will work just as well and comes free with the camera. Unfortunately, for absolute stability, the D90 does not have a true mirror-up mode to settle vibrations before the shutter opens.
Sorry if this reply is late, been out of town. True the D90 doesn't have what would be called a 'true' mirror lock up.
But from the from the manual on page 183 Custom setting d10:Exposure Delay Mode......On can be selected to delay shutter release until about 1 s after the shutter-release button is pressed and the mirror is raised....
Another possibility is to use Liveview to keep the mirror up.