Saying that taste is just personal preference is a good way to prevent disputes. The trouble is, it’s not true. You feel this when you start to design things.~ Paul Graham from, http://www.paulgraham.com/taste.html
I’m not certain about “good” taste. I’m not convinced that there’s an objectively good measure of, well, good taste. I think too much of what some would say is “good,” is actually rooted in the current culture.
But I feel comfortable saying that there is such a thing as bad taste. There are clear reasons, for which one can present a clear case, why things are gauche. There’re clear situations and choices that are in bad taste. Mind you, I can readily imagine art which is intentionally in bad taste; that’s a good thing because art’s purpose is (sometimes) to push the envelope or to change society and culture. But in general, bad taste exists.