One of my sites yesterday had about 64,000 referrals from Google, and just over a thousand each from Bing and Yahoo (and just under a thousand from Baidu).

Google has indexed more than 50 times as many pages as Bing on that site, and crawls far more aggressively (over a million pages per day), which will both be factors, but the main one is probably still that Bing has less visitors.

So for me Bing is still irrelevant as a source of traffic. Even though I'd prefer to see some competition for Google, there just isn't any. DuckDuckGo referred me just 32 visitors yesterday, so they have even further to go!