It's good they discovered something, though the revelation that it's not just a single factor... well that is like a huge "duh" moment. Very seldom, if ever, is a single factor a cause for anything. People seem to like to think that's not the case, but people have a far far over reacting sense of cause and effect. Also, Bee's are the single biggest polinator, but they themselves are not responsible for all the polination. Other insects spread the pollen, birds, the wind... lots of things. Not saying that this isn't important, just saying that, like the scientists discovered themselves, a single factor is not responsible for pollination.
Also, I saw on the page 1 comments that someone mentioned that famous Einstein idea that if all the bees died, there would be 6 years left for humans on the planet. I would like to point out that Einstein's area of expertise was never biology, ecology, pretty much not an expert at anything involving bee's or the environment.
Edit: Just a point of interest. A single population of bees could potentially be enough to undo the damage, so as long as they don't all die, we're in pretty good shape. So that means fixing the problem. If we stop whatever pesticides are mostly responsible (and of course whatever other factor that we have the ability to change), the bee population could make a comeback in pretty short order. Obviously not as fast they dropped off, if only that were possible. There is even the potential to artificially expand the population. For instance, when a new Queen is grown and is sent off to start another hive, they take a sac of sperm with them (essentially). You could grow a queen and harvest sperm from a male source. Then release the new queen in a previously unpopulated area. It is really only feasible because bees are not genetically diverse creatures. For instance, the various classes of bee and ant society are just alternate phenotypes of the queen (genetically identical). The way the genetics work in bees is the queens DNA is completely dominant. Their DNA typically has what is called a genomic imprint marking all the active DNA as being from the queen... from what I have read and understood it to be at least. I could be wrong.