The fifth generation (5G) communication systems have seen initial success in boosting a broad spectrum of mobile networked applications. However, emerging applications, notably immersive eXtended Reality (XR), have already posed significant new challenges to today's 5G given their ultra-high expectations on data rate and latency. They also demand a deep integration of communication and computation for data analytics. In particular, by analyzing the vision data captured by mobile devices, Mobile Vision Analytics (MVA) facilitates understanding of the ambient environment in XR, a key to truly immersive and interactive experiences. In this article, we advocate MVA as a core service of the forthcoming 6G. We closely examine the potentials and challenges of 6G-enabled MVA and accordingly present an integrated framework with massively distributed 6G edge computing nodes to power ubiquitous vision analytics. We identify the critical design issues toward its implementation and shed light on a series of advanced enabling technologies.