The difference is the title. Here it is, No Deals, Mister Bond, with "Mister" spelled out. When the book was released the title read, No Deals, Mr. Bond, using the abbreviation. Exciting, isn't it?
Of course, No Deals, Mr. Bond is generally considered the worst title of any James Bond book. Gardner's working title, which he shared in an interview with The Armchair Detective (Vol. 19, No. 3), was Tomorrow Always Comes, which is certainly better. I've also always thought the villain's name, Blackfriar, would have made a decent title. How they arrived at No Deals, Mr. Bond is a mystery to me.
"The sixth Bond synopsis has been accepted. And I think it will probably be called Tomorrow Always Comes." - John Gardner, November 20, 1985
Visit The Book Bond's special Gardner Renewed page for links to all the John Gardner James Bond reprints in the U.S. and UK.