Yes, you can usually tell the difference between smoking woods. All it takes is a couple of samples and you are on your way to becoming a wood smoke conosuire (SP)
One of the best ways is to over smoke something and get a really strong taste of the wood one time, and then for some reason the taste will be eaiser to recogonize the next time. Juuuuuuuuust kidding. Well sort of, I mean don't do it on purpose that is.
I like to run with Hickory, I don't know why, I just do. Maybe it is kind of the "East of the River Mainstay" Alot of stuff is hickory smoked, so it seems that Hickory is kind of the defacto standard. However it seems that Mesquite is also a standard in another region. Funny though, most regions will tend to use what they have.
A comparison chart may be in order, but it will take a trained palate to describe consistantly the flavors of each wood. And it also is true that some meats do better with specific woods.
I use Hickory for the base smoke description when I talk of other smokes, like saying that Pecan is Hickory Lite or that Oak is Hickory bitter. I think that Mesquite is sometimes Hickory and dust and alot of the fruit woods seem to be Hickory and water, however I swear that I can almost taste apple fruit with apple wood (go figure) I have had Maple go from a very mild smoke all of the way to a very bitter smoke. You just never know 100% what will happen with any given wood or condition