Oddly enough, Santa was everywhere in Noida on Christmas day. He was riding on a bike (that is a real person), hanging body-less in the local market, and wandering about the streets giving candy to children.
Although Christmas is actually a national holiday in India, it is not celebrated by most Indians. Two percent of the population consider themselves Christian. Most of these are clustered in just a few places including Goa, Kerala and Pondicherry. Elsewhere in shops and markets, you see Christmas items for sale to the rapidly growing consumer class. To these folks we believe it is the "festive" nature of Christmas - the colors and lights and gift-giving that are the attraction. But to the average Indian the holiday goes essentially unnoticed.
It's hard to celebrate Christmas in a place that really does not celebate the holiday. I think that the best thing about Christmas in India is that there are no extra holiday pounds to shed in the new year.