So far I've managed to put in 416 hours into the game, across three playthroughs. In my main save file, I currently have 125 hours and 23 minutes (5:5:23:00) clocked in.
Considering I must have slugged at least 2,000 and 1,500 into Fallout 3 and New Vegas respectively, I'd say I've still got a significant bit of my life to sacrifice to this game, especially with the DLC rolling in