A team by team look at the RB situations in the AFC East division
Starter: C.J. Spiller
Backup: Fred Jackson
Spiller is a favorite fantasy sleeper for top 5 RB status in 2013 as the new coaching regime has stated they will get him the ball more and he will be their primary RB over Fred Jackson. Spiller averaged an insane 6.0 yards per rush attempt in 2012 on his way to 1244 yards and 6 TD's. He's also very efficient in the passing game as he caught 43 passes for 459 yards and 2 more TD's in 2012. Now that he will be the definite starter and not splitting as many carries with Jackson, Spiller offers great upside as a starting fantasy RB in 2013. Jackson will switch to change of pace duties behind him. Spiller owners should strongly consider Jackson as a handcuff as Jackson has proven to be an effective fantasy RB when healthy and put in a lead role.
Starter: Lamar Miller
Backup: Daniel Thomas
Expected to be the lead RB for the Dolphins in 2013, Miller has explosive speed and enough size for the position. What is unknown is how well he can be running between the tackles as an every down grinder. He may cede those carries to Daniel Thomas if he doesn't prove capable of being powerful enough inside. It's unknown how well he catches the ball but it's expected he'll operate as the 3rd down RB as well. Miller could boom in the starter's role, or he could end up being incapable of sustaining himself at a high level and need to be part of a committee. Miller is a middle of the road RB2 for fantasy in 2013. Meanwhile Thomas isn't even assured of being the top backup to Miller in 2013 after poor showings the last two seasons. But he possesses superior size to rookie Mike Gillislee and should beat him out for the job. That said, Thomas is unlikely to be fantasy relevant and probably shouldn't be drafted in most leagues unless Miller gets injured.
New England Patriots
Starter: Stevan Ridley
Backup: Shane Vereen
With 1,263 rushing yards and 12 TD's in 2012, Ridley established himself as the primary RB in the Patriots offense. He is their primary RB in rushing situations and also their goal line behemoth. The only thing you could want more from Ridley is a presence as a receiver out of the backfield. He loses value in the PPR format as he only caught 6 passes last season and he will likely cede 3rd down RB duties to Vereen. Otherwise, expect another 1,200+ yards and another 10+ TD's from Ridley in 2013. Meanwhile Vereen's explosive showings as the 3rd down RB in this past post-season allowed the Patriots to part ways with Danny Woodhead and give Vereen the job in 2013. Vereen is a dynamic runner and while he won't challenge Stevan Ridley for early down carries, his abilities as a receiver and occasional rusher could provide him with enough fantasy value to be considered as a borderline RB3/4. In PPR formats, Vereen could be a regular as a flexed 3rd RB.
New York Jets
Starter: Chris Ivory
Backups: Bilal Powell, Mike Goodson, Joe McKnight
Ivory takes over as the new lead RB for the Jets in 2013. While he has proven capable when given opportunities when with the Saints, Ivory has also sustained injuries and it's unknown how well he'll hold up as a featured RB. His receiving ability is also in question as he has caught only 3 passes in his NFL career compared to 256 rushing attempts so he may cede 3rd down duties to another RB on the Jets roster. One thing he isn't likely to cede though is goal line carries. Assuming the Jets can get inside an opponent's 5 yard line, Ivory is likely to be getting all the carries. Consider Ivory a RB3 for drafting purposes with upside to move into RB2 territory. The addition of Ivory says all you need to know about what they privately think about Powell's chances of being a capable lead RB. Powell will battle it out with Goodson and McKnight and none of them are even guaranteed to make the opening day roster. It's unknown if Goodson's impending legal problems stemming from a drugs and weapons arrest in May will affect his chances for making the roster with the Jets or not. Before the arrest Goodson was considered likely to be the top backup and change of pace RB to Ivory. Now it's unknown if his case will be heard before the start of the regular season or not. He could end up being fine during the season; he could be suspended by the league. It's unclear at this time and not worth chancing given his status as just a backup RB in New York anyway. McKnight doesn't get many chances and seems to be perpetually buried on the depth chart despite having shown well in his very limited opportunities. Ivory is the only one you can safely draft.