Note: Well I am not sure if Skype will be able to defend against the telecoms presumed argument that the Skype traffic will overload their existing infrastructure. Personally I would like to see the "walled garden" of mobile networks open up a little as longer as the consumers do not see a huge impact on the quality of service they pay for monthly.
In a move that could benefit end users greatly, VoIP service provider Skype has petitioned the FCC to apply the 1968 Carterfone decision
to wireless phone networks, opening up the possibility of easier use of services similar to Skype on mobile handsets. The Carterfone decision allows customers to attach any device to the phone network, provided it does not harm the network itself, which Skype sees as extending to allow any application to run on any device that can access the network.
Currently, mobile operators limit the kind of data traffic permitted on their phone networks, especially in the case of applications like Skype that can steal revenue from them by allowing cheap VoIP calling. Skype's argument for opening up data networks is that doing so would offer "tremendous new sources of price competition provided by entities such as Skype."
The principal behind the Carterfone decision currently applies to the wired phone network and cable TV networks. Government regulation applying the principal to mobile phone networks would require carriers to allow any application on any compatible handset to be used on their network.
Source: Ars Technica