The good news is that the Eagles didn't squander their cap room like say... the Redskins. Their lack of cap room is due in large part to the several long term deals handed out to young players over the past two years. Not a bad situation to be in. These long term deals to young players have seemed to ensure that while the team doesn't have a ton of cap room right now, they also don't have many needs.
Of course the cap room will probably increase once some of the dead weight is cut loose. Namely, Dhani Jones, Jerome McDougle, Ryan Moats, Dirk Johnson and maybe even William Thomas and Jeremiah Trotter. Trotter and Thomas together account for $7.18 million worth of cap space next year. Trotter, who the Eagles coaches and many fans have admitted is not an every down player anymore and whose knees are really starting to limit his effectiveness... If Trotter does come back next year, there's almost no doubt he'll have to take a pay cut to do so. William Thomas has one more year on his deal and had a great year this year, but has struggled to stay healthy before this year and has highly touted prospect Winston Justice waiting to take his place. If the Eagles don't cut him, they may look to trade him while his value is high.
So even with the seemingly low cap space right now, the Eagles could very well head into free agency with over $20 mil in room to make some moves.... namely LINEBACKER!!!! Using some of that room to bring back Stallworth may not be the worst idea either...