Speaking of tomatoes, cherry tomatoes in particular, those have become a real favorite of mine. I love 'em all, but when I'm making my own salads and want some tomato in them, I've grown to prefer carefully slicing a few cherry tomatoes in half to slicing up a regular one -- unless I intend to use up the whole tomato, in which case I have to figure out the best way to preserve it (because tomatoes lose something in the fridge).
Anyhoo, my point is that for my taste, the cherry tomatoes provide the flavor and juiciness that a grape tomato doesn't. Grape tomatoes are ubiquitous these days, which probably means they're cheaper, and of course they're easy to handle, so everyone uses them as a convenient shortcut. But a cleanly halved cherry tomato (halved, because it's silly to pop the whole thing into your mouth and have to explode it in there to avoid a mess) is the best.
