I prefer vector mapping myself...
While you can make some really cool maps with Photoshop or GIMP (or similar raster applications), I prefer to use a vector app to create my maps. However to many my maps don't look like vector maps - and that's a goal of mine, when I create them. Also I'm a pro fantasy cartographer, I get commissions from many small RPG publishers, but have done work for Dog House Rules, Iron Crown Enterprises, Mongoose Publishing, Conflict RPG as well.
I don't know if its out yet, but I created 289 photorealistic-ish map symbols for Profantasy (makers of Campaign Cartographer map app) for SS3 Modern Symbol Set.
Here's a link to my portfolio here at ENWorld in the Art Gallery board:
http://www.enworld.org/forum/art-ga...inting/257465-gamerprinters-map-emporeum.html
I have many styles that I create as well (all using Xara Xtreme Pro as my application of choice). Some maps look 'photorealistic', but the primary style of mine that seems more sought after is my hand-drawn hybrid digital map. That is all the linework is hand-drawn and scanned. But I place '3D'ish elements, bevels, drop shadows, all coloring, etc. beneath the hand-drawn work.
Between commissions, contests, and personal maps, I probably create 100 maps a year. Lately, however, much of my time has gone into development of classes and settings, as I have moved on from just a cartographer, to being a third party publisher. I enjoy all such creative endeavors.
Heck, its an advantage for me as a 3pp. Most publishers can only afford 3 or fewer maps as maps are one of your more expensive content for commissions for publication. My first adventure features 10 maps, because it ain't nothin' for me to create them - and I can standout against the competition.
GP