@ Tilt... What you say is true of the regular contributors. However....What percentage of people who have logged in over the past couple of months actually post and contribute? 5% ? 10%? Everyone else is trawling for free tutorials and maps. Many of those people would be downloading art without really reading any of the posts, and are not aware that the usage of those images is restricted. They are probably going to many other sites too. Soon they have a folder full of pretty maps and can not remember where they got each individual image. Often there is no signature so how could they know? A few weeks later they find themselves on another site with a bank of images. So they upload some from their folder and download some from the site. And so on.
There is nothing obvious in place to warn people from doing this innocently or prevent them from doing it deliberately. Now with the new gallery up it will be much more prevalent because casual users will have much easier access to the maps without even seeing the license requirements in peoples sigs. (if that even makes a diference)
Personally I don't care who uses my maps...I wouldn't post them if I did (which is also why you will never see pictures of my children on the internet). But for you pros out there I guess that it is one of the drawbacks of posting on the net. Have you gotten more work from posting here than you would have otherwise? Is it worth taking the risk of copyright breaches to get your work out there?
One more thing I will say though is that the more generic and easily adaptable the map is the more people are going to want it. I've noticed that the unlabeled WIPs are downloaded a lot more than the finished maps. That's why I like to post raw versions, so they are useful to others. A simple watermark over your work will deter most people from taking the image because they are looking for something quick and pretty...not an afternoon of doctoring each image in photoshop.