What would you consider a thinking-person's thriller?

DeNiro's performance is THE best rendition of that particular character that I ever expect to see. Ever. Nailed it. Retired it; and, on the shelf next to it in my library are Al Pacino, Viggo Mortensen, Gabriel Byrne and Jack Nicholson in the same role.

But, Angular, if you allow including Angel Heart, which is aces with me, then, The Exorcist.

I've seen it countless times and it's still relentlessly featured on one of my movie channels. Agree with your assessment, btw.

Yes indeed
A very good script and story choice
I love horrors and thrillers but most of them seem to neglect the 'holy crap im up against a maniac' aspect and instead rush to the heroic climax
Real life isnt like that
The original book by Robert Graysmith tells it true...the hunters of The Zodiac wound up drunken, divorced or depressed...with no awesome climactic battle
The Zodiac must be dead by now and im glad he is
Chilling stuff

I love the moral ambiguity Scorsese brings to his remake. Sure, the movie can get over the top and cheesy (it's Scorsese's bid at slasher genre legitimacy after all) but at its core there's a fascinating moral quandary at work, one that I feel Nick Nolte did an excellent job illustrating. No good guys, in fact, exist in the remake -- which is a far cry from the original and its clear delineation between Peck's starchy righteousness and Mitchum's evil incarnate act.