Or the most probable thing is that someone internally was annoyed by the bug and got permission to release. A single update to a 10 years old camera on an apparently abandoned product line is not something that gets a big amount of PR coverage, especially since nikon DLSRs had very few updates ever. Unless it is part of an up-and-coming new updating scheme (which I very much doubt), it will not make much difference except a little goodwill from D7100 owners.