I've had experience in the last six months at BWV, HH, and VB. In all cases, I was able to connect using either a local call or a toll-free "800" style number. I was charged the $0.35 per call charge.
I did not have any success getting "clean" lines. In almost all cases the modem would have to drop the connection speed down, sometimes even to 14.4. This may be due to jacking in on the phone, rather than a direct wall connection.
I'd recommend bringing a long phone cord, as Disney has not installed the telephone (and thus the connection port) in a location that is friendly to using a laptop. Often the phone jack is near the bed and across the room from the table / chair.
Vero has a "business center" with connections, but they want a rediculous rate of $10 per use.
Cap