I can't find any sign that the update has been sent out. It's not mentioned on the B&N website, and I have not found anyone who reported having installed it.
So far as I can tell this rumor was fiction. Told you so:
The reason I disbelieve this rumor is that Nook Media has shown every sign that they no longer wanted to sell ereaders. That is my explanation for adding Google Play, an update which changed the Nook HD from an enhanced ereader into an Android tablet. That is a marked difference from this rumored update which would turn the Nook Touch from an ereader into an ereader plus.
I also think Nook Media passed on using the 6.8? screen, and don’t forget that Nook Media’s current pricing policy suggests that they are clearing out existing Nook hardware at a loss. In fact, several retail partners no longer carry the Nook Touch or Nook Glow.
If Nook Media is getting rid of Nook ereader hardware then does it really make sense for them to invest time and money in a new firmware update for a soon-to-be dead device? And we’re talking about a 2 year old device, at that.