The Orioles are a terrible ballclub and it says a lot that the Red Sox struggled to beat the Birds 2 of 3 at home.
The Orioles are not as bad as their record. They have a good lineup with solid hitters (although they miss Brian Roberts). Tejada and Markakis have always hurt the Yanks and Ty Wigginton is doing very well this year. They have four solid starters with decent ERAs, and the Yanks catch three of them on this trip (Millwood, Guthrie and Brian Matusz). Their bullpen is legitimately awful, and is largely the reason for their miserable record - but you can't always count on comebacks against a bad bullpen.
I'm actually very worried about these next three games. Everyone assumes the Yankees will roll, but the games won't be easy. The O's are due to start playing well. Last year, the three games that terrified me the most were the home games with the Nats. I posted that those games worried me, and everyone "pooh poohed" me. Well, the Yanks lost 2 of 3.