One of the greatest hindrance to ecommerce, based on my personal experience, will be the unreliable courier service.
For example, I ordered an item online on eBay.in 21 July 2010 (can provide the Paisapay id if required) , it was shipped on 23 July 2010 with docket no. B3224*** to be delivered in the same city Mumbai.
It was not delivered on 24 July 2010 , since the courier service suddenly found the address inadequate. They had been delivering parcels to the same address satisfactorily earlier.
Again on Monday 26 July 2010, they have not delivered claiming it was closed, when I was at the address provided the entire day(all 24 hours). A person will shop online only if the entire experience is hassle free.
If certain courier services in India are unreliable, most online shoppers will think twice before making a purchase online and waiting for up to a week (or may be more) for delivery.