Difficult to tell, but here's the score from IMDB:
The Departed 8.4/10 (47,938 votes) top 250: #80
Internal Affairs 8.0/10 (10,903 votes)
http://www.movie-remakes.com also voted The Departed as "Better than the original".
http://www.movie-remakes.com/film_detail.asp?id=157