WiFi as substitute for 3G causes MNO's some big problems. Yeah, yeah, I know you knew about it for the last 5 years. The point is that with analysis like this:
"..."Head-to-head competition with DSL or public wireless LAN could kill profitability. Such strategies may fill 3G networks with low-margin internet traffic, leaving no space for more profitable services such as voice telephony, small-screen messaging and video content
...Several operators are experimenting with time-based and unlimited-usage tariffs. Such schemes may be simpler for users, but they inevitably jeopardize revenue per MB, and hence profitability."
it's no surprise they're getting killed - nobody wants to contract with firms whose strategy is simplistically measured by 'revenue per MB'; they want to contract with innovators who expand the pie, not keep it deliberately shrunk.