Sorry Gozar, but I'm gonna have to be ones to say "SHUT UP!"
I think "one of us now!" is a fairly decent translation of that line, plus the context of that scene should already tell a reader that Nami is now gonna be part of Luffy's crew, I personally don't find it taking anything or adding any more to the emotion of the scene.
Also, like it was mentioned before, "nakama" is a Japanese word. So would it not make sense to translate the word into an understandable context? As far as I'm concerened, nothing's happened to the English manga significant enough for me to bitch about. (cursing is something more subjective, and it's not like thier calling alcohol "power juice")
I swear, we already have the Narutard subbies in this world to sweat over minor crap.