This pick makes a ton of sense after the Ravens lost guard Ben Grubbs to the Saints in free agency. Zeitler steps in and takes over the position. The Ravens rarely let players walk without a plan to replace them, so I wouldn't be surprised by this pick at all.
SB Nation's Ravens blog, Baltimore Beatdown, explains the pick:
The Baltimore Ravens need to find a replacement for left guard Ben Grubbs, who bolted for the big bucks in free agency to the New Orleans Saints. The Ravens have mentioned trying last year's 3rd round draft pick, Jah Reid, into that position, one that he has never played before. Ironically, the choice here was between Zeitler and his Wisconsin teammate, center Peter Konz. Konz is leaving college after his junior year and has been recovering from a dislocated ankle that kept him out of the second half of the 2011 season, and disappointed at the Combine in the bench press, putting up only 18 reps. Zeitler, which had 32 reps at the Combine, is a mauler while Konz is more of a wall-off blocker, which is not what the Ravens need in putting a lot of emphasis on the running game. Zeitler led the nation for knockdown blocks with 142 and had 33 blocks that led to touchdowns. This draft pick will be the type that the Ravens "plug-and-play" right away as soon as he hits the team's practice field.