I'm just cutting and pasting from the Football Outsiders site.
Biggest hole: Running back
The Cardinals are still expected to cut veteran Edgerrin James, although they have not yet done so. Rookie Tim Hightower, who replaced James in the starting lineup for part of last season, was the second-worst running back in the league (minimum 100 carries) in both of Football Outsiders' advanced statistics, DYAR and DVOA. (Only Cincinnati's Chris Perry was worse.) Third-down back J.J. Arrington has left for Denver. Suffice to say, the Cardinals have a need at this position.
The 2009 draft is not particularly stocked with running-back talent, especially compared to last year's phenomenal class -- but that may actually work in the Cardinals' favor given that they will be picking at the end of the first round. Chris "Beanie" Wells clocked around a 4.40 40-yard dash time at his Pro Day and is shooting up draft boards, so the Cardinals will have to trade up if they want him. That leaves the two other "elite" backs in this draft: Knowshon Moreno of Georgia and LeSean McCoy from Pitt. Moreno possesses Barry Sanders-like lateral quickness, and although he lacks elite speed, the Cardinals should snap him up if he falls to them. As for McCoy, he has great hands, but he is undersized and struggles with pass protection. The Cardinals already tried this experiment with Arrington, and there's no reason to try again.
Free Agency Recap
As always, the Cardinals were relatively quiet in free agency. After dithering around for a few weeks on Kurt Warner's new contract, the front office managed to add cornerback Bryant McFadden to help shore up the secondary and play across from rookie phenom Dominique Rodgers-Cromartie. The team also added journeyman running back Jason Wright, who should enjoy his year playing lots of special teams, where he will likely be joined by former Rams tight end Anthony Becht.
As for depatures, the Texans' signing of defensive end Antonio Smith was probably the biggest loss, though certainly not a devastating one by any stretch. The Cardinals also won't miss Arrington, linebacker Monty Beisel, or cornerback Eric Green (now of the Miami Dolphins) either.
I like this breakdown, think it's pretty accurate. Only thing I disagree with is any mention of McCoy as one of the "elite" backs in the draft.