Class of 2012 and no early decision

The latest Tiger E-News had the headline "Freshman class ranks as Princeton's most diverse" with the text:

"
Princeton has enrolled the most diverse freshman class in its history for the third consecutive year, selected from a record-high number of applicants following the University's transition to a single admission process. The class of 2012 includes record representation of students from minority backgrounds and international students, has the highest percentage of incoming students to receive financial aid and, for the first time in University history, is evenly balanced in terms of gender.
http://www.princeton.edu/main/news/archive/S22/15/15O66/
"

If you follow the link, the article goes on to give numbers about how various indicators continue to shift slightly in the direction of greater class diversity, but the most interesting number shifts aren't acknowledged: 

                2012    2011    2011ED   2011RD
                -----------------------------------
#applied        21370   18942   2276     16666
#admitted        2122    1791    597      1194
%accept          9.93    9.46   26.2      7.16
#matriculated    1243    1246    597       649
%matriculate     58.6    69.6    100      54.4

(ED=early decision; RD=regular decision; also note that the article says there were 1838 admitted to the class of 2011; however that doesn't match up with the 9.4% overall acceptance rate; http://www.dailyprincetonian.com/archives/2007/05/18/news/18499.shtml shows the correct(?) number of 1791.  Early decision numbers taken from http://www.princeton.edu/main/news/archive/S16/64/75S14/index.xml?section=newsreleases.)

At any rate, no surprises that the total number of applications were up and the overall matriculation rate was down.  At first I was a little surprised that the overall acceptance rate actually went /up/, but suppose that's an artifact of the increase in the number of applications not catching up with the necessary increase in the number of admissions (due to a lower overall matriculation rate) to obtain the "correct" number of incoming students.

I was also initially surprised that the matriculation rate for the class of 2012 was so much higher than the rate for non-early decision students in the class of 2011, but then remembered this is probably due to the fact that there are a certain number of people in the class of 2012 who knew they really wanted to go to Princeton and would have enrolled early decision had that option been available.

Something to keep an eye on as the kids get closer to college age, and of course fun for anyone who likes to look at numbers.  Now I want to go hunting for the Harvard rates...