OP, despite the thread title, no one can make the decision for you (it's unfortunate). I just recently ordered a MBP 15" i7 and while I can't tell you what to do (I've used a matte PB for five years and just ordered a matte MBP - so I'm a little biased), hopefully I can give you some thoughts for thinking through the decision.
I went to the Apple Store and had a look at the two screens side by side and, if there's one in your city, I'd suggest you do the same. You'll get a much better feel for the screens that you will looking at photos on the forums. People claim the glossy screen's blacks are blacker and colours are richer, but I wouldn't infer from that that the matte screen is washed out and subpar. I personally think the matte screen is a great display and, when you look at it, you don't think that the blacks are any less black and colours are any less vibrant than they ought to be. Like anything, it depends what you intend to use it for - if colour accuracy is important (for something like print media/design), you may want to look into matte, if you want to watch movies in the dark, go glossy.
Additionally, you've got to consider where you're going to be using it. I think it's great what you did with the HP, but actually sit there and see what it would be like using a glossy screen in that location at different times of the day. I borrowed my brother's glossy MBP for a little bit and tried it out on my own desk, only to realize I'd be staring at the ceiling light behind me over my right shoulder for the next number of years (I'd go mad...so that's when I realized I'd be going matte again). Similarly, where I usually set up in my kitchen, I'd be looking out a large window through my screen when not otherwise staring myself in the face. If you don't have these issues (like some people claim to), then glossy will probably be great. However, there's no point (or I fail to see the point) of getting what may end up being tantamount to a mirror-finish on your screen. I don't know how often you're mobile with your laptop, but also consider that you'll never have full control over lighting and possibly not even where (or what direction) you'll be sitting.
I've just never had a great experience with a glossy screen - it seems like I've always been looking at the ceiling lights, myself or whatever is behind me. Some people seem to be able to look past this or don't see it at all, and I think it depends what you're used to. I'm not used to it, so it's distracting for me and I find it difficult to get any work done (design, word processing or otherwise). I have friends that swear by glossy screens, but that may be because their first laptops were glossy macbooks. If you're used to it (or just not used to a matte screen), then it may be fine for you.
Ultimately, I don't think it's a terrible exercise to consider when you're going to regret one option over the other. I for one am only going to possibly regret going matte when I'm sitting in the dark, watching a movie and wondering if it looks any better on a glossy screen. But then there are these things called televisions...and they're pretty good for watching movies on, so I don't know. I certainly don't work in the dark and don't think it's right to have to adjust how you work (shutting shades, turning off lights, rotating desks -- like some people have been suggesting) for the screen on your laptop...it just doesn't make sense to me.
Glossy screens are great in the right lighting conditions: darkness. That's why Plasma TV screens are glossy. If you're like me though and are neither nocturnal nor work in a cave, you may want to consider the benefits of a matte screen.
Best of luck, OP. Try to get your hands on a MBP with a glossy screen to borrow, if only for an hour, to test out the screen. You'll be able to make your decision easily then.
