High costs of subscriber acquisition coupled with extremely ambitious targets have seen many an MVNO burn cash like there's no tomorrow. Indeed, apart from Virgin Mobile in the UK, there aren't too many successful MVNOs across the world. Of course, there are some of the smaller, interesting and arguably successful examples across some of the Benelux countries, and then there's the new kid on the block, Blyk.
India's experiment with MVNOs, although still caught in regulatory and inter-departmental conflict, will be quite interesting to see. With limited uptake of data services, and a larger problem surrounding scarcity of spectrum, it will surely take some serious thinking to break the MVNO conundrum !