Pros
Decent compensation package, nice benefits, Annual raises usually around 3% to 4%. Yearly bonus usually between 7% and 13% (dependent on company performance metrics) Good severance package (50% of your salary as long as you've been an AT&T employee for 13 years, with gradual lesser increments for less time served)
Cons
Don't believe the fake news: You can take all the AT&T University classes you like, but there is no migration path for legacy network personnel to fill all the new jobs in next-generation technologies. (Cloud, Software Defined Networks, etc). Instead, the company is hiring fresh-faced affordable college graduates, and laying off thousands of dedicated technical folks in their mid-50's. " AT&T is gambling that future profits will be able to pay the current huge debt-load from questionable acquistions: Time/Warner, U-Verse, etc.