One of the recurring themes of conversations with persons from mobile operators at 3GSM is what’s going to happen with instant messaging and Skype. People (at least the limited subset I’ve met) were talking about announcements such the 3/Skype announcement and IM interoperability but no-one seemed sure what it means. The general impression seems to be that if operators go for this business, push down data tariffs and don’t try and impose charges per message or whatever then they will grow the market but cannibalize SMS revenues. I’m more of an optimist: if O2 had Skype and IM interoperable with AIM/MSN on a 3G phone, then they could charge me £20 per month for a 1Gb data package. If they charge me 10p per message for an IM that isn’t interoperable with Skype/AIM/MSN, then their revenue will be 0.