Yesterday I was playing around in the front yard with the new D90 and trying to get some good close-ups of dandelions (I didn't) and just generally trying to get to know the camera. After I'd crawled around on the front lawn for an hour or so, I took a break and happened to look up and saw the late afternoon sunlight coming from behind my Japanese maple. I'd been out in the yard for about an hour and really paid much attention to the tree, but when the sun got low enough, the leaves and tiny buds just began to catch fire and it was very striking.
Strong backlighting and translucent subjects like leaves or flower petals are a great combination because the light makes them appear to glow from within. Exposure is straightforward as long as you keep the light source (the sun) out of the frame, but you can experiment with using exposure compensation if the shots look a bit too dark--try adding a stop to a stop and a third of additional exposure. The background was somewhat dark behind these leaves so I didn't have to use compensation because the darker background fooled the meter into thinking the subject needed more light. Had the background been brighter (a bright grassy lawn, for example), then I might have had to use compensation. Just experiment or bracket your shots and you'll find out what works.
Speaking of the D90, by the way, the one feature I don't like so far is the LCD--which seems far too bright to me. I dimmed it down to the -2 position (you can adjust the brightness of the LCD on this camera) and still it seems a bit light too me. I love the size of the LCD (about 3") because it's like looking at a projected image the size of a small print--very impressive. But I'm not happy with the brightness issue and I'm goign to ask around to see if anyone else has the same complaint. Let me know if you've noticed it. I never had the problem with my D70 cameras, so I'm surprised. I'm going to do more testing this week. Other than that though, so far I love the camera.