There's little arguing that on paper, the Orioles don't appear to be better now than they were last season, but they can still lay claim to having the best defense in baseball.

ESPN’s Buster Olney points this out, naming the Orioles as the best defensive team in baseball in his Top 10 defensive rankings (an ESPN Insider subscription is needed for the full article). The Kansas City Royals, Atlanta Braves, Arizona Diamondbacks and Texas Rangers round out the top five in Olney's rankings. The Tampa Bay Rays rank sixth.
In fact, the Orioles may have gotten better defensively this offseason.

The Orioles’ defensive accolades have been well documented. Third baseman Manny Machado won the American League Platinum Glove as the league’s top overall defender in his first full season in the majors.

In 2013, the Orioles won three Gold Glove awards, tied for the most in baseball, with Machado, shortstop J.J. Hardy and center fielder Adam Jones all winning. They recorded a major-league record 119 errorless games and committed just 54 errors, the fewest in a 162-game season.

Six Orioles were named Gold Glove finalists, with second base and left field being the only non-pitcher positions not to be nominated. All six of those players return, and a look at defensive metrics show that the Orioles are better in 2014 at the other two positions.
While former Orioles left fielder Nate McLouth did win a Gold Glove in 2008 with the Pittsburgh Pirates, new acquisition David Lough -- who will likely share time in left with Nolan Reimold and Steve Pearce, as well as possibly Francisco Peguero and Henry Urrutia -- is an upgrade defensively.