John Lim has been reading tea leaves and predicts that PHP5 will be stable within 5-8 months.

I am not sure if I totally agree with his conclusions. PHP5 is helped by the fact that it contains stable code from PHP4. However, since PHP4 is stable and people are generally happy with it, there will be less people using PHP5 in a production environment, which could translate into longer time periods before bugs shake themselves loose.

Like John said: all predictions are useless, but it is fun speculating, even when you're wrong.