Lost Alpha is an ambitious mod for Shadow of Chernobyl that aims to recreate all the content that was cut from the game between alpha and release. New (old) areas and new (old) mutants are the main additions, with the bulk of the mod being recreations of the cut locations. The team are aiming to stick as close to the original versions of the cut content as they can based on known info and it's all looking mighty impressive. After a long time in development, release is closer than ever, which has of course been true every minute since it was first announced. We should have a date in February. In the meantime, here's a trailer and a FAQ.
Even mod trailers have grufty voiceover men now. I shall consider hiring one to announce my arrival at social events.
As for S.T.A.L.K.E.R., I've been considering a new mod loadout at some point and if this turns out to be less than a couple of months away I might end up waiting for it instead.