Well, not really. His name comes of twice. One of the characters in the "Under the Dome" book is Dale Barbara, an ex-military officer who had served in Iraq and apparently worked with Jack Reacher in the past. Dale Barbara and another military character in the book have referred to Jack Reacher twice and what a great person he is.
I am enjoying it. Is not scary at all. It is more of a "Lord of the Flies" kind of thing. Adversity strikes a town and they are all trapped and then you get to read the dysfunction fall out. Power hungry, corrupt individuals taking over the town, murders, survival, and of course the good people trying to survive. The scary, supernatural part hasn't really come out yet (and I don't know if it will) but it is definitely a "what happens when society unravels" kind of book.