Here are all the places I lube my RD - that is, all the places that are visible in this picture. There are also four pivots on the rear of the body, and of course the other side of the lower jockey wheel and both sides of the upper jockey wheel. ONE DROP ONLY on each point, work the part to get the oil inside, then wipe off the outside.

Even if the bearings are sealed (or ceramic bushings, as I have on my upper jockey wheel), a drop of oil will help maintain the seals. I wouldn't grease them unless I disassembled them and could make sure the grease stayed on the inside of the seal, because outside, grease only collects grit.
It's true, the lubricants you use do depend on where and in what weather you're riding. My lubricant needs are different in Florida (salt air and fine sand) than they are in Ohio (farm dust), and someone who often rides in wet weather will have different needs from a rain weenie like myself.
Pedro's makes two non-toxic lubes. The lighter weight one is called Go! That's the one I use, and I really like it a lot. It lubricates well, goes on very light, and doesn't collect excess grit. The heavier one, for wet weather riding or mountain biking, is called Chainj.
WD-40 is useful for cleaning tar off vehicles, and old built-up chain lube off the motorcycle. It's also useful as a penetrating lubricant for stuck fasteners, which is what it's actually intended for. I don't use the stuff otherwise, and I make sure to wash it completely off any painted parts as well as any parts that need lubrication.
WD not only evaporates within a week or two - leaving parts unlubricated - but while it's there, it collects lots of grit. Exactly what you don't want on moving parts.
Also, as I said, I'm a weather weenie and much of my riding is done in a low-grit environment, so my chain doesn't get cleaned that often. If I were doing it every 100-150 miles, I wouldn't re-lube the derailleurs every time, just make sure to wipe and brush off any grit.
Last edited by OakLeaf; 07-26-2010 at 04:31 AM.
Speed comes from what you put behind you. - Judi Ketteler