I reckon if you go to the trouble of making a map you should sign it somewhere eh, ur ingame name, ur avatar or some symbol.
In reality its like a little artwork, this thing you have created, you should sign it in some way.
Don't forget ppl will download it, and some of the maps will end up on other servers of course. "Your" map could end up being the favourite map on someones server or even get to the point of being a popular map on heaps of servers, who knows?
You may end up with a map as popular and well known as shotty, deagle, or churches etc.
And they wont know who made it or where it comes from.
Thats what I reckon anyway