Yes, they have. If you are using the Thompson modem provided my them you can check. Go into the router with your browser and type 192.168.1.254. Once inside click on broadband connection on the left side and it will tell you how much speed you are getting. Mine was at 2mb last week and i just check and these are the results

Bandwidth (Up/Down) [kbps/kbps]: 638 / 4.832

so yes, I am on 4Mbps now