Well first of all, if Vodafone has to make it a real deal, they must provide at least one unlimited plan for their GPRS services. The current plans of Vodafone are plain pathetic while their competitors like Airtel and even IDEA has got Unlimited Plans on their EDGE Services. For a person like me, who remains out, not frequently, but for long times whenever i go, Vodafone's cureent plans can't work out. On IDEA at 20 Rs per day, i do unlimited surfing mostly at the speeds of 128-165 KBPS. SO even while they also dont deliver the promised 246 KBPS, they have atleast usable speeds at affordable, unlimited plans. And with 3G this becomes more relevant.
@the.kaushik: ya man, i too read something like that long before. Speed of a 3G network is limited to 384 kbps AFAIK and above that the service is provided as HSDPA which is a 3.5G technology (i could be wrong).