HSDPA taking over from ADSL?

According to the GSA Secretariat, HSDPA upgrades have been made to over 200 3G networks across the world.

Offering up to 7.2Mbps download speeds (ok theoretical speed), all forms of HSPA networks be they slower or faster are rapidly replacing fixed broadband as the price drops and flexibility increases.

Increasingly households are replacing desktops with laptops and using cheap dongles as their main means of internet connection.

So why pay BT for the privilege of a telephone line when it is rarely used (mobile & Skype replaces calls) and the broadband speeds BT supplies are often slower than HSDPA anyway?

(ed : Many financial services including banks require that you have a landline number, furthermore, bandwidth sensitive, time-critical services like Video on Demand are better served by cable and landlines for now at least)