Nope... there are still people signing up for dial-up accounts on a daily basis in masses! Even dial-up AOL and MSN accounts... ewwe!!!
Not everyone can get DSL/Cable/Broadband... either because of financial reasons, (although most high speed services are getting real cheap), or because the service isn't available in the area where they live... so until then... 53kb is the limit, assuming the phone line isn't a real shitty one full of line noise and shit causing it to go down to 26,400 baud...