On Saturday Nationals' President Stan Kasten spoke to fans (and 20-odd bloggers) before the Nats-Reds game. He covered a range of topics from the Philly Phan Invasion to Strasburg-mania. He also touched briefly on Bryce Harper.
Speaking in the abstract, because this was 24 hours before Mike Rizzo confirmed what everyone has known for months, Stan noted that Harper's path to the majors would be greatly accelerated by moving out from behind the plate. Based on his "conversations with baseball men" Kasten observed that a young catcher could take 4 or 5 years to develop.
On the other hand, an outfielder with Harper's bat and physical tools could conceivably be major league-ready in two years. So there you have it. The plan all along was to draft Harper, move him to right field and have him playing behind Strasburg and Zimmerman by 2013. Dave Cameron has some thoughts on the pros and cons of this approach here.
Stan also repeatedly mentioned that "signing quickly" would be key to Bryce Harper's development. Way to play it cool, Stan.