[fz_rider]

Pirelli will take over as the sport’s sole tyre supplier from 2011, following Bridgestone’s decision to withdraw at the end of this season. The Italian company will provide all teams with rubber for the next three years, in compliance with existing F1 sporting and technical regulations.

Source : Formula 1? - The Official F1? Website

[nitrous]

They have been out of the sport for 20 years almost.
God knows how they're going to develop compounds for 2011.
I'm guessing they're going to have complaints for atleast half a season.

[Newpunter]

I think it will be a good thing if they make crap tyres. The current Bridgestone tyres are too good and there is not enough tyre degradation. Case in point, yesterday, Kobayashi did 53 laps on one set of tyres and would have easily completed the whole race on those tyres if not for the mandatory 2 compound rule. We need tyres to degrade more to make the races interesting like in Montreal.

[nitrous]

Originally Posted by newpunter

The current Bridgestone tyres are too good and there is not enough tyre degradation. Case in point, yesterday, Kobayashi did 53 laps on one set of tyres and would have easily completed the whole race on those tyres if not for the mandatory 2 compound rule.

Credit that to super smooth driving putting on consistent, conservative laps and the choice of hard tyre compound by Bridgestone.
Its pretty easy to mess up tyres in just a couple of 'qualifying laps'.