nuketown is one of the best free for all maps in gaming history, hence why so many people played it and it was usually voted the map-to-be-played sometimes 10 games in a row until they made it so it couldn't be played that many times in a row for the few people who didn't like it. thats how i saw it anyways. maybe you are talking about the new nuketown ( then which i know nothing about)
it was a easy map too farm xp an if your pro versus noobs even more xp they made it were you could not keep picking it because handful pro's would keep picking it an farming the noobs making it less fun as their no variety in maps
it got extremely competitive amongst the pros. that's all i know. and thats the only reason i played it so much because it'll make you a quicker, more precise shooter. but of course you need to incorporate skills in other areas such as strategy in demos and flag based games.
This was the highest online voted map, it was the only map that I would get stuck playing for like 2hrs straight because the lobby picked it over and over again. It wasn't my favorite map, but the community spoke and said loud "WE FUCKING LOVE NUKETOWN" ......