On the LA freeways it can be too busy and hectic to do the wave thing. Sometimes on the major streets too. After that it breaks down to the usual variations.
You get some snobs that couldn't possibly wave at a "commoner" that paid so much less than they did, and on the other end of the spectrum there are some folks that wave like cheerleaders at a pep-rally.
I'll almost always wave if I see that the other rider is looking (and I'm not in the middle of doing something), usually the low-down two-fingers-for-two-wheels wave.
I like the friendlier types in our biker crowd. As long as it works for you, there is no such thing as the "wrong" kind of motorcycle.