Expensive unlimited? After hearty $3.92 billion profit, AT&T shares surge the most in 8 years

Despite that, or maybe precisely because of the fact that its unlimited data plan is the most expensive still, AT&T is again laughing all the way to the bank compared to the other major carriers, as we have shown you before, as the exodus of phone plan users last quarter was not as major as analysts predicted, and was offset by a big jump in tablet plan subs. AT&T reported earnings that beat analysts' expectations Tuesday after the closing bell, scoring a million more wireless net adds than expected.

What's that in terms of money? Well, the carrier made $39.84 ...