Photoshop about 10 to 14 hours a day here (professionally that is). I work on an iMac 27" i5 and a new MBP 15" i7. Debated for a while on this matter, and ended getting the glossy MBP screen.
The reflection issues are minimal for me (move a little bit/tilt the screen), especially compared to the iBook g4 I've had for many years (matte screen on that...since back then "Matte" was what you got) and I much prefer to have a consistent environment between all my work stations.
Now, if I could get myself a powerful mac with a large IPS monitor (HP ZR30w whaaaat), I might say otherwise.
In all honesty, if you're a *Serious* photographer / graphic artist / designer (or any visual art) you should have a static screen/ workstation (to work on more than a 15" or 17" surface). If you can't, the glossy vs matte debate should really come down on where you will use it (I.E. : do you work mainly on your balcony? In a weirdly lit office? A dark basement?).
I can say that, whether I'm using a matte, or a glossy...when there's reflection on either of them, I can't work properly (the matte has this big, soft-ish "hot spot", while the glossy is simply a specular reflection).