Lets get into it. I'll start with his size, 6'2" and 231 lbs. In the modern NFL, every backfield is going to see different backs throughout the game (even McKinnon will see the field and he's behind AP who is arguably the hardest back to get time behind) so, for the majority of the time, it is bigger backs that get utilized in the running game and more importantly, in the redzone. I hate putting so much emphasis on the TD heavy players because I understand that backs who specialize between the 20's (like I expect Abdullah to do) are just as important, but its just how the league has progressed.
Now I'll talk about where his head is at, which is something that always means a lot to me (but is always hard to precisely pinpoint). His name on all social media outlets is "blessedmj" which can be done by anyone, but its a good sign nonetheless. More importantly, he did not get in trouble in college (which I don't think even I could do, going to the University of Florida). There is much to be discovered on this front but he's doing things right thus far.
He's made the most of his opportunities in camp and preseason, just check his stats (mostly against 1st team defenses) and the hit he laid on Kevin Johnson in Hard Knocks, it was nasty.
The coaches constantly preach about him when he comes up. He also got two rest days back-to-back, something unseen for backs but a great sign that they plan to use him Week 1. Which brings me to my next point.
He's guaranteed third down snaps and will eat at Morris' carries from Day 1. Morris is as solid as a back can be, so that's Jones' biggest threat.
Lastly, the dude runs as downhill as any runner I've ever seen. Check out his tapes.