I play wurm for almost 2 years now. First of all, Wurm ain't a game, it's a simulation (MMOFS - mmo fantasy simulation, at least thats what dev consider it to be ). In Wurm not only the towns are player made. 95% of the game is player made. Each building, wall, fence, road is built by players. Also all the tools and items you use in the game are created by players. There are only few items that are purchased from NPCs (for example village deeds, that way you can claim some land, depending on size of the deed, as your own and set your own rules). You can also build towns without deed thing but then you have no guards to protect you from wild life and any1 could come and mess around.
There are no levels at all in Wurm. There are lots of skills and you can practise any of them without any limitation. Your skills and atritbutes rise as you perform them.
There are 2 servers: PVP and Non-PVP. On pvp server there are no safe zones at all. You have to build your own safe zone Tall walls, guard towers, all sort of fortifications, secret underground entrance, it's only limited by your imagination You can travel between those 2 servers as many times as you want, but it takes time. There are no ships or teleports like in EL. You have to cover all the distacne on foot. both servers are 10 square KM maps, so there is a lot of walking.
2 problems I can see in Wurm are: little player base: there are about 100 players online at a time on non pvp server and 50 on pvp server.
Other thing is that this game is improving too slow. There is only 1 guy working on server code, and 8 or 10 ppl working on client. Besides these, Wurm is a perfect game to play. It's one of a kind.
Ooops, I get a feeling this post is a bad off top