Edge network is already available in Metro's and some A class towns like Pondicherry and all tamilnadu district headquarters. It is up to your handset to have edge feature. Having Edge should drastically change the data transfer speed. But the service providers in India doesn't seem to give stable connection speeds.
I once found that my edge enabled Sony ericsson w810i connected to my laptop (AIRTEL MOBILE OFFICE)was downloading at the rate of 25 KB/sec... un belivable... But I couln't see that speed again. Normally the transfer speed would be 10 KB/sec
ps: I am talking about the DATA TRANSFER SPEED.. Don't mess around.