This according to Reuters, which notes that Bugatti's old-is-new-again CEO Wolfgang Dürheimer is keen on hybrid propulsion as evidence that the Alsatian marque is likely to pursue such a powertrain for the Veyron's replacement. The system wouldn't help curb the Veyron's portly weight, of course, but it would likely help cut down its prodigious fuel consumption. The current car, by the way, would run dry after 12 minutes at its 250+ mph top speed (by which point the special Michelin tires would have melted anyway). More importantly – and more likely – the hybrid assist will make the new car even punchier at low revs.
Of course, even assuming Reuters is correct, there's no telling to what internal-combustion engine the electric motor in the next Veyron will be paired with. However, considering the massive sums of cash Volkswagen spent on developing the unique 6.0-liter quad-turbo W-16, we'd bet it'll use some form of the same – just with an extra jolt of electric power thrown in for good measure.