Mods are just Fads, everyone gets excited, full 200 servers within the first week, then they gradually become bored of it.
It's a vicious cycle. Not saying it will happen to IE but it's happened a lot.
Depends how you treat it. If you treat it like an extra thing along the NW events it's doomed to fail.
There's some regiments that only play N&S and they have fairly popular events. I even attend them myself. The reason people think mods die is because public play dies out. This is because most mods are focused on events (where the real enjoyment is in my opinion).
We could solve this by implementing an invasion gamemode. I have suggested it several times with various responses. Just look at
Full invasion 2. It has alot of public play going for it.