There's no technology justification for a differentiation between the cost of call termination on mobile networks and fixed networks, and in this respect, this article is right.
Where there is a case for differentiation is obvious. If you make a local fixed line call, even between two operators, you're only using a very small part of each of their networks. The whole call should probably cost you 10c, so why should the interconnect part be as much as 20c? (In contrast, it's impossible to know where a mobile phone is on another network - it could be anywhere in the country - so the rate needs to take this into account, and reflect the average cost to deliver the call anywhere.) This is not in any way a difference in the cost of the infrastructure (as the mobile operators argue), merely the way that fixed line and mobile markets work.
What making the rates the same would do would be to artificially RAISE the fixed line termination rate to match the (cost based) mobile termination rate, since the latter is required to be a cost-based national (NOT local) rate. The knock-on effect would be to raise the retail price of local fixed line calls, which is definitely not good for consumers.
One industry expert pointed out that it is already possible to use a mobile phone with a Vodacom SIM card in it to make a voice call over Wi-Fi without ever touching the Vodacom network. This converged fixed/wireless network clearly demonstrates the futility of trying to classify a network or call termination as fixed or mobile, he argues.
This opens a much more complex debate. The question that you need to ask is, "Who is paying for the access infrastructure that is carrying the call?" (This would normally be how one determines the actual cost on which a termination rate should be based.) On a mobile phone, basically it's the user on the mobile network, who is paying for their data service (whether 3G or even on WiFi). Hence, why on earth should the (over the top) VoIP operator get any money at all for terminating this call? Look at Skype, for example. The FCC in the US has concluded that, in the case of broadband (and the logic works just as well for mobile broadband), the cost to the (VoIP) operator of terminating calls rapidly approaches zero, using a standard Long Run Incremental Cost model. Hence, the termination rate on VoIP should be ZERO.
