When I was in college, my girlfriend owned a 1986 Volvo station wagon affectionately nicknamed "The Box." Its exterior may have been decidedly boxy, and the engine whined when you tried to start it on a winter morning, but The Box displayed one particular advantage: the then-16-year-old vehicle refused to die, no matter what anyone tried to do to it. Despite every catastrophe that life could toss at that two-ton hunk of metal (thrown rods, clogged tubes, frayed wires) it kept chugging along a mile at a time.

In that way, Bing is a lot like a 1986 Volvo station wagon: despite predictions of its imminent demise ever since its release, Bing has kept on chugging. (One of those predictions, actually, is hilariously ironic in retrospect: Yahoo CEO Carol Bartz predicting during the Bank of America and Merrill Lynch U.S. Technology Conference on June 3 that interest in the search engine would be "temporary," although that might have also been an attempt to throw anyone off the scent of an impending Yahoo-Microsoft search-and-advertising deal.)

New figures by Experian Hitwise for October suggested that Microsoft made a 7 percent month-over-month gain in U.S. search-engine market share over September, hitting 9.57 percent of the market. By comparison, both Google and Yahoo saw their respective shares drop by 1 percent, to 70.60 percent and 16.14 percent.

Once that aforementioned Yahoo-Microsoft search-and-advertising deal is completed in 2010 (nothing so far indicates that the U.S. Department of Justice or anyone else will hold up the agreement on a technicality), and Bing powers backend search on Yahoo's pages, Microsoft's search-engine market share could rise to close to 30 percent. Microsoft CEO Steve Ballmer has claimed at various points that the added information flowing into Bing from Yahoo's pages will allow them to improve the search engine in possibly dynamic ways, but whether that will start to threaten Google is a wide-open question.

Bing is adding new features through the end of the year, including local news and weather, an expanded video page and search results from Wolfram Alpha. I'll make an easy bet and say that those features will allow Microsoft to either hold its recent gains, or else increase its share by another point or two before New Year's Day.

Some commenters may opine that one research note does not a trend make, and that's definitely true. But I think we've received enough data over the past few months to indicate that Bing has been making slow but steady gains even as Microsoft's larger marketing campaign winds down. Like a certain car, it keeps on puttering away.