I posted earlier in the year about the BICEP2 experiment's claim of detecting evidence of cosmic inflation. Since then, there's been a bit of a storm-in-a-teacup (fanned by blogs like mine and the media) over whether or not it's real. While the title of this BBC article is easily misinterpreted, it's a nice piece showing "science in action".
The main issue that cropped up is that dust emits a polarized signal the has to be removed in order to see the faint fingerprint of cosmic inflation (the "B-mode" polarization signal). Data from Planck -- a space-based mission also attempting to detect B-mode polarization -- has recently shown that the dust signal is more polarized than the models BICEP2 used in their analysis.
The BICEP2 group has now officially published their findings in Physical Review Letters, and have conceded that given the new Planck data, their confidence has gone down. Fortunately, we won't have to wait too long to find out: Planck are busy analyzing their data, there is data from the Keck telescope, and BICEP3 is to be deployed this Antarctic summer.
We're going to need confirmation by independent groups. That's the way things work in science. We don't believe things because somebody says they're true; we believe them because different people make the measurements independently and find the same results.