They now have one at North Point Mall in Alpharetta, Georgia. My impressions after about 20 minutes of doing a side by side (literally) comparison of the 15" vs 17":
1) the screen on the 17" is dimmer than that of the 15 inch. Someone else in this thread also mentioned that, and that's what I saw as well. I turned up the brightness all the way on both and the 17" was noticeably dimmer. In high ambient light situations, that extra bit of pop could come in handy in fighting reflections on the glossy screen.
2) I now realize just how much more information you can pack onto the screen when you're talking about 1920x1200 vs. 1440x900. I had always told myself that the screen sizes are physically not that much different, so what's the big deal? Resolution is the big deal. It makes (in my opinion) a world of difference. I had macrumors open full screen on both (with the dock hidden) and you could see six more thread titles on the 17".
3) While noticing the smaller font (due to the higher resolution) on the 17", I thought about this quote...
Sir Cecil said:
The highest resolution on the 17" is not ideal for comfortable everyday viewing of websites, text documents etc. I'll be using a lower setting for general use (still higher than the 15"), but use the highest setting when it's necessary, for images or fitting multiple items on-screen.
The beauty of it is having the choice, according to the need of the moment.
...and I could see Sir Cecil's point. So I started changing the resolution, trying to find something that was as pleasing to my eyes as the font size on the the 15" macbook pro. My conclusion regarding using non-native resolutions: eeeeewwwww

. It looked like garbage and I can't imagine many people will use anything but 1920x1200.
Final thoughts: this is a nice notebook for which I have absolutely no need (see my sig for my other macs). And I was all set to buy a refurbed 15" macbook pro (which is already overkill for my needs). But I *really* liked what I saw today, and I have the money to get it, but...damn....gonna have to think about this some more...