Most of the net groups organising Bechdel tests haven't actually claimed the test demonstrates a movie's quality, feminist leanings or strong writing. They often specifically state that the test has no relation to those whatsoever. Yes, you would be an idiot to use the Bechdel test as a, well, acid test for movies...but most feminists don't. The people who put the chart together was simply pointing out that, for the first time, movies that passed the Bechdel test outsold those that didn't.
That definitely doesn't indicate a difference in quality or a trend towards feminism in cinema, but I argue it displays a shift in the make up of audience demographics, tastes, and the way movies are marketed. Over the past few years, big movies that try to appeal to female audiences have been more and more financially successful. That may well be the one thing you can thank Twilight for; it proved to producers that it is economically viable to spend big bucks, making movies that aim to interest women. Traditionally, the biggest budget, biggest profit movies have a tendency towards testosterone fuelled, man action, but now we are getting more sci-fi and fantasy movies - the genres traditionally reserved for young males - that put women in the spot light. Those movies are clearly getting a bigger audience share for it.
The Bechdel test is useless for examining the strengths of individual movies - it is more focussed on the broad aspects of movie making...but so are producers and studios, who are also recognising the benefits of acknowledging women as a target audience, which ultimately means providing more female characters, more interesting female stories, and hell, even sticking in more fan service for women.