I've got LCD TVs, which I preferred to plasma TVs because of the glossy vs. matte issue. So when I started looking at MBPs I felt sure I'd prefer the matte. When I compared the two in the Apple Store, with all the lights, I initially liked the matte better because of the glare. But when I sat the glossy MBP beside the matte MBP the colors on the glossy just "popped" to me, looking so much better than the "washed out" color of the matte screen. So I debated and debated, read many threads like this one, and went to the Apple Store about a dozen times to compare the matte vs glossy MBP. After pondering, I boiled it down to my head said get the matte, but my heart said get the glossy.
I ended up going with my heart and the glossy 17 inch MBP and I've never regretted it! The colors are so nice on the glossy screen. The first week I used my MBP was at night at home, with normal overhead lighting and lamps. And that first week I kept asking myself whether this was really a glossy screen, because in normal use I couldn't tell unless I angled the screen just right to catch the glare. The next weekend, when I first used my glossy MBP during the day, I saw more glare, but it was not very noticeable except when the sun was streaming in the windows behind me. During those times I just changed the angle of the screen slightly and eliminated the glare.
Since I've gotten my glossy MBP I've had the chance to look at other glossy screens, mainly Dells, HPs, and Compaqs, and to me the PC glossy screens were much more reflective than the Mac glossy screens. I don't know whether that is right, but to me the Mac glossy screen is not as reflective as PC glossy screens, at least the ones I've seen.
So for me, I'm glad I went with the glossy. I love my glossy MBP! But the bottom line is there is no right answer and no wrong answer--there's only the right or wrong answer for YOU, and what you prefer! Some swear by the glossy; some swear by the matte--go look at them in the Apple Store, or find someone with one, and look at it, over and over, in all conditions, and decide which YOU prefer!