Julio is probably definitely gone. I'd say 95% and the only reason I don't say 100% is because I believe he'd truly rather come back but it's in his best interest to go. He's NFL ready and will be a top 10 pick, top 20 for sure.
I would say Ingram is next on the likely list, probably at 90%. The injuries have held him back this year, but he'll be healthy in the spring when they do all the draft evaluations and he's a first round pick for sure. Likely the first RB taken.
Dareus is next at 85%, IMO. Yes, he's been "missing" this year but he's been double-teamed most of the time and he's battled injuries as well. He's got first round talent if healthy, probably top 10 if he does well at the combine.
As for guys like Hightower, Barron, and Upshaw, I think it's 50/50 and probably less that they leave. Hightower is still not healthy and he has some work to do to improve his stock. Barron as well. Upshaw would probably be a 2nd/3rd round pick and you are generally advised to play your senior year if that's the case.
And having said all of that, I honestly believe none of these guys are eager to leave. We as fans may sit here and think that, but I believe they geniunely love it at Alabama and would come back for sure were not it for the uncertainty of staying healthy while playing a violent game. It's always a risk, and some will decide to stay, some will decide to go. This season will no doubt sting for all of them, and it will cause them all to seriously consider redeeming themselves next year. In the end, I think Julio, Ingram and Dareus go pro, but only because their stock will be high and they've done all they can do at this level to improve it. It wouldn't shock me if any or all of them come back, but I expect them to go and I wish them all well. They deserve it.