As a Redskins fan we likely don't even have the wins we have without Desean. Dude no lie is open for a deep pass at least 3 times a game. Someway somehow our QBs seem to not be able to get him the ball. They constantly overthrow, underthrow or completely don't look his way.
Do the Eagles miss Desean Jackson? Sure, I mean any team that loses there #1 WR for nothing will. The Ravens still looking for an Anquan Boldin replacement [Steve Smith?]
Do the Eagles NEED Desean Jackson? This is difficult question. Originally I was going to say, no they don't they're record shows they're doing just fine w/o him. But, if they want a chance to compete with the top teams in the NFC they actually would have needed him. Look at their record, they've basically only won against trash teams. 6 wins against teams that don't have a record above .500, the trash afc south, and division rival Cowboys. With losses to the entire NFC west except STL and Green Bay.
With that said no team is as explosive without Desean Jackson, dude has been the most dangerous deep threat in the league his entire career.