Last year if I remember correctly, the fever zone was pretty much "free game", everyone just found a space to stand roughly behind a seat. Security was awesome about it, and the ones that didnt want to stand were happy to find another seat, sometimes even in a better viewing location. The way that Ticketek is handling it this year is very similar, with the same sort of promotional messages and pictures as last year. I just got an email about stadium protocol and there was a bit about the fever zone in it.
The only problems that i can see with this year, is the fact the zone has moved closer to the halfway line, and is in a more desireable area, thus more unaware punters that may be unhappy to move.
On the day, i would suggest waiting til close to kick off, find a spot in the zone, and just stand there until you get told to move. You always have your seat in 406 to fall back on if security is a bitch.
(Ps. Last year I asked for a seat in the fever zone and i got placed right at the back next to the acessability seats, so i just moved closer to the action right before kickoff and no one moaned)