I am under the impression that methane levels in the atmosphere have spiked significantly in the last decade or two, and the origin is not really understood. Extraction could be one source, but if it's from another source, that could be more bad news as it would mean that some tipping point has possibly been triggered. I'm far from an expert on this though.
Most of the consciously vented is flared. However, the infrastructure leaks like mad and there have been no incentives incentive for the companies to fix it, it's a cheap invisible gas after all with almost all reporting being self reporting.