Google Sites ranked as the top search property worldwide with 87.8 billion searches in December, or 66.8 percent of the global search market. Google Sites achieved a 58-percent increase in search query volume over the past year. Yahoo! Sites ranked second globally with 9.4 billion searches (up 13 percent), followed by Chinese search engine Baidu with 8.5 billion searches (up 7 percent). Microsoft Sites saw the greatest gains among the top five properties, growing 70 percent to 4.1 billion searches, on the strength of its successful introduction of new search engine Bing. Russian search engine Yandex also achieved considerable gains, growing 91 percent to 1.9 billion searches.
Not the most appealing thought for me either Alcoholico, but strictly from a marketing standpoint adding facebook updates (or something...anything unique) into serps would add some value and raise awareness of Bing existence--which Bing desperately needs.
As it stands, Bing offers no point of differentiation at all relative to Google's serps, which means little chance for organic growth.
There's really no compelling reason to make a switch.