In general, there are a few rookie standouts each year in the NFL, but it seems that the 2006 rookie class was pretty good when measured in terms of immediate impact on teams (as opposed to long-term success, which is how rookie classes are normally judged). Usually it takes a season or two for a rookie to become a true pro and contribute on a regular basis. This is partly because of the greater physical demands of the pro game, and also because of the complicated play schemes that pro coaches use. Defensive linemen in particular have to go through a period of adjustment, because they generally tend to get manhandled by veteran offensive linemen down there in the trenches. This article on the NFL web site outlines some good theories on why rookies were so productive in 2006.
One thought I have (which may or may not be an original one) is that it seems coaches are more concerned about keeping their star players healthy by rotating them in and out more and spreading the workload. At least it seems so at the running back position when you consider running back tandems Reggie Bush (rookie) and Deuce McAllister of the Saints, Laurence Maroney (rookie) and Corey Dillon of the Patriots, and Maurice Jones-Drew (rookie) and Fred Taylor of the Jaguars. It's not a new thing to rotate players in and out, but to me it seems a little more frequent lately. Just a thought.
For a little reminder of who was picked in the first round of the NFL draft in '06, check out the 2007 World Almanac page 925.
