Well, and I think Fox is using an aggregate of polls, not just the last single poll. And in the aggregate, Jindal's still down with Graham, Santorum and Pataki at the kiddie table. Christie is qualifying with a mere 2% support, so it wouldn't take much of a shift for Christie to fall out and someone else move up, except that reaching 2% would basically be a doubling of their current numbers. Honestly, I think they'd have been better off to include a 5% threshold or something to winnow down the number of candidates. Under that scheme, the number of debate participants would be down to five: Trump, Carson, Cruz, Rubio and Bush.
Last aggregates have Trump narrowly in the lead nationally but still losing in Iowa (though the most recent PPP poll has Trump narrowly ahead in Iowa). For now, Trump has a pretty solid grip on New Hampshire, South Carolina and Florida, so even if he loses Iowa to Carson it's no big thing (and would be in keeping with Iowa's history of often picking eventual losers). We have to face the growing reality that Donald Trump may be the GOP nominee for 2016. He still has plenty of potential to fuck it up for himself, but given the electorate and his natural base, I'm not sure there's any kind of gaffe that will cost him significant support, unless he's caught in a three-way tryst with Obama and Hillary while signing a deal buying illegal immigrants from China.
Also, Clinton is back up to a 30-point cushion in national polling, and a whopping 57-point lead in Georgia, which at the moment looks like it'll go red anyways.