Depends. One is permannent, the other is temporary. Hence the "temp-ban" expression. Maybe suspension would be more accurate and it is a difference of terminology on EW and the OTT.
Well, "IP Ban" is a standard expression; it's a standard function in forum software. It's not a "WotC term" or an "EN World term", it's a "that's what that phrase means in the context of messageboard software" term. And an IP ban isn't permanent; it doesn't have a duration attached to it. I could prove it to you by IP banning you from here for 10 minutes, but that would be rather silly.
Oh, god, I've bored even myself. My brain has just shut down. Have I really been talking about this for the last hour or so? There really was nothing on TV tonight....