This was the source of a great deal of angst and debate for me before placing the order. I originally thought I wanted a 17" matte so I could more easily do initial photo review/correction in the field. In the end though, the extreme size of the 17" made me choose the 15" for portability and greater usability on a plane/in my house/at Starbucks. Going to get an ACD for more screen real estate, and use that for critical color work.
Also, FWIW, I got a glossy screen as well. Not what most "pros" would use, but it looks really good, and I can actually see it out in the daylight.