I've been keeping up on this and I don't believe it to be what Wired speculates (though I've seen those rumors myself). The generally accepted answer to this seems to be that the Redbull's engine (Renault) cuts half its cylinders[0]. Yes this can be seen as a type of _torque_ control, not traction control.
The sound was what my engine sounded like when a spark plug cable came loose and thus not firing the cylinder.
As for why Webber doesn't sound like that - well you can speculate that Webber just doesn't have the trust in his car as Vettel has to get on the power that early. And, if you've kept up with this season at all, you'd understand why Webber has no trust in his car[1].
The sound was what my engine sounded like when a spark plug cable came loose and thus not firing the cylinder.
As for why Webber doesn't sound like that - well you can speculate that Webber just doesn't have the trust in his car as Vettel has to get on the power that early. And, if you've kept up with this season at all, you'd understand why Webber has no trust in his car[1].
[0] http://www.roadandtrack.com/go/news/racing/red-bull-traction
[1] https://scontent-a-lax.xx.fbcdn.net/hphotos-frc1/600837_1010...