Add salt and pepper to taste, but why?

in addition to the comments so far (do see the dickerman article), if you want to see how a little bit of black pepper brings out the flavor or a good, try a small amount on a dessert of strawberries with a final gilding of whipped cream.

Thanks for the article link, Pegeen. The history behind "salt & pepper to taste" is really interesting. I agree so strongly with Dickerman's statement "I think we’d appreciate pepper's qualities all the more if we used it just for specific dishes, not universally." A few years ago I started using pepper only when I specifically wanted its flavor, and it really has had this effect.
I think everyone should try skipping the pepper in the kind of lazy "salt & pepper to taste" that ends so many recipes, unless you really want that specific flavor, and allow the other seasonings to come through more clearly. I also really like using the various chiles mentioned in the quote Pegeen posted to provide a little final zip with a different flavor.

This Slate article does a good job explaining how salt and pepper wound up on the table together. The writer's thought is that while the right kind and amount of pepper does give most foods a needed brightness, through history, we wound up using the wrong kind of pepper for that.
http://www.slate.com/articles/life/food/2012/01/salt_and_pepper_why_are_they_always_together_.html
In her last paragraph:
"Tabasco is close, though. I would argue to replace tabletop black pepper with one of the dried chili varieties that are cultivated in the Mediterranean. Maybe piment d’espelette, the Basque chili pepper; or Aleppo pepper, the lemony Syrian kind; or, best of all, Marash red pepper from Turkey, which holds just a modicum of heat in its dark red flakes, but also a sort of cherry-toned fruitiness and a pleasant orange-pith bitterness. Is Marash red pepper arcane? Yes. Esoteric? Yes. Difficult to find at the store? Yes once more (though you can order it online). But it is wildly versatile and hard to overdo. I’ve never met a pot of beans, a chicken soup, or a green salad that didn’t taste better with some of these flakes sprinkled on top. It works in pork stews, on lamb, on buttered carrots and eggs. Even a 20-pound pot of mashed potatoes would taste better with a spoonful of Marash pepper. If only I’d known this when I was working at Spago." - Sara Dickerman

Salt accentuates the flavors of the dish, pepper adds a subtle pop, almost like inviting your taste buds to wake up pay attention. One thing to remember is there are many kinds of salt and pepper. Typical table salt and black pepper bring one flavor. Pink or black salt I like for things like salads, and prefer tellicherry pepper for almost everything.