This is an older article..
I think I’ve addressed this question before. My feeling is that it’s strong up to a certain point and it’s a cop out for Microsoft to be using this as an excuse. I’m not doubting the power of data and feedback loops but Bing has enough scale and traffic and they have a lot more low hanging fruit to pick than Google.
Also remember that Microsoft has access to people searching on Google so they have a lot more data than the queries being performed on Bing.
Once it starts, this cycle of prosperity snowballs — more users, more data, and more ad dollars. Economists call the phenomenon “network effects”; business executives just call it momentum. In search, Google has it in spades, and Microsoft, against the odds, wants to reverse it.