Away from the political backlash against its entry into India, the world's largest retailer has been keeping domestic rivals guessing about the format it would adopt in this country, where grocery shopping is an industry by itself.Wal-Mart, better known for its large stores like hypermarkets and supermarkets spread over thousands of square feet, may go in for the neighbourhood store format keeping in mind the Indian consumer's preference for this model."We expect Wal-Mart and Bharti to explore the neighbourhood market concept because groceries are one of the largest retail categories with the least organised retail competition in India," Love Goel, a former Wal-Mart adviser and US-based global retail investment firm and chairman & CEO, Growth Ventures Group said.Though foreign multi-brand retailers are barred from setting shop in India, Wal-Mart has tied up with Bharti Enterprises to gain a toe-hold in the country.Even though fully opening up retail sector to foreign players still remains an issue, domestic petrol and petrochemical major Reliance Industries has entered the field and already boasts of over 40 neighbourhood vegetable and grocery stores across five cities.Wal-Mart, which has a revenue of $320 billion, is the largest retailer of groceries in the US. So, it could be anybody's guess what format it would choose for India.