If they decide they need to be sellers and they trade everyone in the bullpen except Patton and Strop they would still be in good position bullpen wise next season and beyond.
Strop, Patton, and then guys like Socolovich, Hunter, Steve Johnson, Bergesen, Berken, Gonzalez, Pomeranz, Burke, etc. could still be a strong bullpen. You figure Arrieta at worst would be a great reliever going forward, same with Tillman, and not all of the young pitchers can be starters in Baltimore as there is only 5 rotation spots.
Dan Klein could be back next year and maybe ready for Baltimore in 2014, Erbe is a project but maybe he works out as a reliever, Wada should be ready for next season, and there are a bunch of other guys in the minors that could make it as relievers. I'm not exactly sure how minor league free agency works though. Pomeranz, Gonzalez, and Socolovich I believe all signed 1 year minor league free agent contracts. Does that mean if they are on the 40 man they would still be on the O's and just have no options going forward or are they free agents at the end of the year even if they are on the 40 man? Either way, the team has bullpen options going forward thanks to Duquette's love of depth.
Again, most wouldn't bring back big time packages but Johnson may be able to get us a top 100 prospect. Koji brought back Hunter and Davis last year, and I believe Mike Adams cost the Rangers a pretty penny as well. Maybe a team in the hunt becomes desperate for relief help like the Rangers were last year and the O's can take advantage of that.
I'm not sure what hitters would bring anything back though. Roberts has not looked good, owed a good bit of money, and is old. Reynolds is a horrible defender but can get on base and has crazy power. Wilson Betemit isn't necessarily good anywhere defensively but he is alright at the plate and can play multiple positions. Markakis is owed a lot of money.
Adam Jones just signed the big contract so he isn't going anywhere. Wieters, Davis, and Hardy aren't going anywhere either.
Hammel would bring back the best return but if he is interested in staying in Baltimore he would be a fine #2/#3 pitcher going forward for the next 4 or 5 years. Chen isn't going anywhere as his contract is incredible. I don't imagine they will give up any of the young pitchers if they decide they aren't going to compete this year and will likely give them all opportunities to show they should be on the team next season.
Actually, after typing this all out I'm in favor of trading most of the bullpen even if the team continues to stay in contention.