A couple of my best friends went to see Rocky Balboa on Christmas Day and came back debating over the reason why Talia Shire did not participate in the film. According to them, it came down to two reasons: The female of the group thought that, perhaps, time hadn't been too kind to Shire, and therefore she wasn't crazy about appearing on screen as Adrian. Seeing as the woman has acted in a number of films since Rocky V, that argument was rather silly.
My other friend felt that it had more to do with story; that Sylvester Stallone wanted the film to feel powerful, and so the only way to accomplish that would be to leave Shire out of it. I've heard some people claim she wanted nothing to do with the film, others said she hated the script and forced Sly to work around her character -- all of it adds up to a number of theories most moviegoers probably shared with one another as the final credit sequence rolled. Well, USA Today managed to grab Shire for a few moments during the Rocky Balboa premiere (she originally declined Sly's invitation because she was afraid the film would be too emotional of an experience for her. I shall not delve into the reasons why it would be too emotional because they could spoil the flick for those that haven't seen it).
So, why was she cut out? Why wasn't Talia Shire asked to return for the final installment of the franchise when she had appeared in the five previous films? Well, you'll have to head on over to USA Today to find out -- though keep in mind, there are spoilers.