In 2009-10, the full professors were Anthony Appiah, John Burgess, John Cooper, Dan Garber, Gil Harman, Mark Johnston, Alexander Nehamas, Gideon Rosen, and Michael Smith; the associate professors were Adam Elga, Delia Fara, Hans Halvorson, Hendrik Lorenz, and Ben Morison; and the assistant professors were Shamik Dasgupta, Mike Fara, Liz Harman, Des Hogan, Tom Kelly, Boris Kment, Sarah-Jane Leslie, and Sarah McGrath. Daniel Cloud and Victoria McGeer were lecturers with the rank of professor, and Frank Jackson and John Hawthorne were visiting professors. Jeremy Butterfield gave the Carl G. Hempel Lectures.
The noughties were notable for the appointment a number of assistant professors who were ultimately given tenure: Adam Elga, Hans Halvorson, Elizabeth Harman, Des Hogan, Tom Kelly, Sarah-Jane Leslie, and Hendrik Lorenz. They joined the ranks of several others in the department who were promoted after being assistant professors: Paul Benacerraf, John Burgess, Gil Harman, Mark Johnston, and Gideon Rosen. Two others—Delia Fara and Michael Smith—had been assistant professors, but left before coming up for tenure, and then returned later to tenured positions. This means that, at the end of the noughties, only five faculty members—Anthony Appiah, John Cooper, Dan Garber, Alexander Nehamas, and Ben Morison—hadn't once been junior faculty members of the department.
The decade also saw greater cooperation with the University Center for Human Values. Philip Pettit and Tori McGeer entered into an arrangement whereby part of their regular teaching for the UCHV was done in the department, and two philosophers were appointed jointly. Liz Harman was the first person given a joint tenure-track appointment with the UCHV. Her appointment was also remarkable in part because her father, Gil Harman, was already a department member. More about this can be read here and here. Anthony Appiah's high-profile move from Harvard to a joint appointment with the UCHV ushered in a period of extraordinary productivity for him. By the time he left Princeton at the end 2013, Appiah had published five new books: Thinking It Through: An Introduction to Contemporary Philosophy (2003), The Ethics of Identity (2005), Cosmopolitanism: Ethics in a World of Strangers (2006), Experiments in Ethics (2008), and The Honor Code: How Moral Revolutions Happen (2010). You can see Appiah talking about The Honor Code at a book launch in Cambridge, Massachussetts, here (skip to 7:00 on the video).
The noughties also saw the retirements of Harry Frankfurt, at the beginning of the decade, and Paul Benacerraf, at the end. Benacerraf, who Ray Monk describes as having "one of the most penetrating minds in contemporary philosophy", retired after a 60 year unbroken association with the University that began when he came to Princeton as an undergraduate. You can read an interview with him here. Frankfurt became something of a celebrity in retirement after his essay "On Bullshit" (1986) was republished as a book by Princeton University Press in 2005. You can read about Frankfurt's appearance on The Daily Show with John Stewart to talk about On Bullshit here.