VoIP vs evil roaming costs

In the wake of 3's abolition of roaming charges, the CEO of internet telephony provider Coms (nope, me neither) has issued a rather triumphalistic statement about how it's all the result of operators "feeling the squeeze" from VoIP.

Interestingly, Terry Martin seems fairly certain that Vodafone will be next to drop the cursed fees, and notes that "it will be interesting when the mobile operators have to start looking at partnering up with each other in order to survive".

Chiding operators for shelling out billions on 3G licences thanks to "over-enthusiastic forecasting" then trying to claw back money by screwing the customer (not my words or Martin's, but T-Mobile's), Martin goes on to call 3's new tariffs "a cosmetic offer to try and deflect criticism", showing "they have a long way to go to match the new wave".

Ignoring the fact that 3 is actively promoting the use of VoIP on its new handsets, and is including this functionality in its roaming-fee-free new tariffs, I'm a little uncertain as to how much impact VoIP has really had on the mobile operators' core roaming haul. Perhaps I'm behind the times, but is the Club 18-30 set of early 2007 really phoning home from Mallorca using Skype headsets?