Its predessasor gives 22 kms per ltr on highways & 17 kmpl in cities. I feel this is a very good average. If this car also performs like this it will definately popular. From my experience I feel new Alto will also perform like its predessasor.
Good Luck to Maruti & its users !
In the age of high petrol price, people would like to own maruthi alto for daily commutation to office. They would probably have an another sedan for family occassions as status symbol. If the price is competetive, first time, low budget buyers will defenitely go for it.