Per Jon Heyman's twitter account, the New York Mets have refused to include Zack Wheeler in a trade package for Justin Upton. As a result, it seems unlikely that the Diamondback outfielder will be moving to Queens for 2013. Upton previously excercised his limited no-trade clause to nix a deal to Seattle that would have sent Nick Franklin and one of the Mariners top pitching prospects (either Taijuan Walker, James Paxton or Danny Hultzen) to Arizona.
Upton would have immediately alleviated some of the Mets outfield issues as he is both right-handed and a very good defensive rightfielder. He's also only 25 and signed to a reasonable contract through 2015 (~39 million per Cot's). Upton has, however, been a devotee of the Brett Saberhagen performance model, alternating years of average performance with all-star level ones, so there is a bit of risk here to go along with MVP-level potential. Apparently, the cost ended up being prohibitive for the Mets front office and that seems to me to be a reasonable stance. Most prospect pundits have Zack Wheeler as a Top 10 prospect in all of baseball, give or take a few spots, and the Georgia right-hander is very close to major league ready. Even given the Mets possibly replacement level outfield, Upton alone is unlikely to put the Mets over the top in the next two or three seasons, especially once you subtract Zack Wheeler from the equation, and given the team's precarious financial situation it's unclear if they could afford to extend him past that.
It's doubtful that a deal built around Noah Syndergaard or Travis d'Arnaud would be amenable to Arizona, so the Mets will have to look elsewhere in this quest to find a major league outfielder.