The only updated info is that Motorola announced a couple of weeks ago that the Turbo would be updated directly to version 5.1. Neither Motorola nor Verizon ever give timing. You'll know when you start seeing stories about Motorola inviting members to soak tests. As soon as those invites go out, within hours there will be a post here about it, if the past is an accurate predictor of the future (which I think it is in this case.)
Hold tight, it's coming. We don't know when, but it's coming. (Followed inevitably by the people complaining about the update, who they want the old version back, etc.)