JetBlue and United Airlines have unveiled a new collaboration, Blue Sky, to offer customers expanded travel options and greater loyalty rewards. The partnership is pending regulatory approval and will allow passengers from both carriers to earn and redeem miles or points across each other’s networks. United’s MileagePlus members will be able to use their miles on JetBlue’s routes to the Caribbean, while JetBlue’s TrueBlue members gain access to United’s vast global footprint. The integration of loyalty benefits....