According to Trekcore's facebook page, Unification is getting the special single disc release. The only thing I don't like about that aspect is I will probably not buy the signal disc release and I will miss the special features about Spock. Darn them for that.
"Unification" would certainly sell better than "Time's Arrow" as a single disc release, they can put a nice big picture of Spock on the cover. I can see them doing a new Nimoy interview as part of the extras.
Target will probably have their save $10 deal again when you buy it with the S5 TNG set on release week.
The thing is I've been getting gift cards from Christmas/Birthday so I would rather get it through Amazon. I got BOBW with the Target deal and that was nice, but I'm not sure when I would ever put that disc back into the blu ray player again. Now, if they did this, and then at the end of the release they had a bonus release of all the single disc special features, I would probably buy that. That actually wouldn't be a bad idea and it's another revenue source for them.