Found a interesting reading from a link posted in indiegamer forum. They say

Five years ago, those same people were making millions telling
everyone how their new dot com alone was going to have a 30% market share.
Digitally distributed games today account for one on-hundredth of that one
percent. Is it growing, sure. Will it be much bigger in five years? You bet.
But the reality is that customers will be downloading Madden 2010 from a
retailer’s website, not the developers.

Well, I partly disagree. If you take Madden for sure, but because is developed by big software house. But in future I see more chances for independent developers. Fun how anyone seems to have forgot what happened with Doom first and Quake then… those games were first ESD and then came to retail…!