According to Culpepper’s rapsheet on nfl.com, his fumbles come out to exactly 1 per game. Scope it out:
Games played: 81 (started 80)
Career fumbles: 81 (33 lost)
Career INT: 86
Sooo…that’s an average of 1 fumble per game, 1.06 INT per game, and a total of 2.06 per game. Considering less than half of his fumbles were recovered by opponents, it’s an actual turnover rate of 1.65 per game.
For comparison (all according to nfl.com’s stats…not all of which add up, so this is rough):
Tom Brady- .83 (66 INT, 1 fumble lost, 80 games) and one punt for 36 yds 
Marc Bulger- 1.45 (51 INT, 13 fumbles lost, 44 games)
David Carr- 1.03 (53 INT, 9 fumbles lost, 60 games)
Jake Delhomme- .98 (52 INT, 1 fumble lost, 54 games)
Brett Favre - 1.36 (255 INT, 53 fumbles lost, 225 games)
Brad Johnson- .93 (102 INT, 20 fumbles lost, 130 games)
Peyton Manning- 1.01 (130 INT, 0 fumbles lost [!], 128 games) This guy’s TD to INT ratio the last three years? 3.5…outstanding.
Donovan McNabb- 1.04 (66 INT, 32 fumbles lost, 94 games)
Steve Mcnair- .95 (103 INT, 30 fumbles lost, 139 games)
Jake Plummer- 1.18 (148 INT, 2 fumbles lost, 127 games)
Vinny Testaverde- 1.31 (261 INT, 33 fumbles lost, 223 games)
Mike Vick- 1.01 (39 INT, 20 fumbles lost, 58 games)
Conclusion? I dunno. Culpepper’s got a very high turnover-per-game ratio. Even Jeff Blake is a 1.40. Aaron Brooks is an ugly 1.68. I think it’s good to bear in mind that Culpie played 7 games last year and had 15 turnovers. He never got a chance to even things out (not that I care, I’m a Green Bay fan). David Carr has what looks to be a reasonable t-over rate, but his teams usually stink. Favre has a much higher rate and he’s been to two Superbowls, won one. Other factors definitely play into this.
This statistic alone will not determine any QB’s success. I don’t think it’s a good indicator of talent. Aaron Brooks and Daunte Culpepper are not comparable QBs.
It’s a good stat to argue about over beers, though. I love trivia.