It has a reputation of being solid, but passive.
Reputation Philidor defense

It's reputation has improved over the decades due to entering it through a Pirc move order 1. e4 d6 2. d4 Nf6 3. Nf3 e5 or 3...Nbd7

As far as I know the Hanham still has it's solid reputation, white gets nothing more than a very small edge. You still see the occasional big-name GM play it from time to time.
http://www.chessgames.com/perl/chessgame?gid=1790504
http://www.chessgames.com/perl/chessgame?gid=1772475
A relatively recent book on this sort of thing is A Cunning Chess Opening for Black by Sergey Kasparov.
"International Grandmaster Sergey Kasparov (1968) was born in Baku, Azerbaijan, and now lives in Belarus.He is the author of the successful books The Dynamic Benko Gambit (2012) and Steamrolling the Sicilian (2013), as well as numerous Yearbook Surveys, all for New In Chess."
A relatively recent book on this sort of thing is A Cunning Chess Opening for Black by Sergey Kasparov.
A review can be seen at
http://www.jeremysilman.com/shop/pc/Cunning-Chess-Opening-for-Black-A-76p3899.htm
So I was wondering what the reputation is nowadays of the Philidor's defense?