Before anyone gets too excited I'd just point out that all they have found is a rocky world within Proxima's habitable zone. That doesn't mean that world necessarily has a breathable atmosphere, water, sufficient gravity, a geomagnetic field, rotation sufficient to distribute heat equitably across its surface (as opposed to it being tidally locked facing Proxima), or any of a dozen other features requisite to support life.

Oh... and did I mention that Proxima is a known flare star?

Wake me up when they find a terrestrial world in the habitable zone of Alpha Centauri instead.