I actually have a bit of a different opinion on this. First, regarding Wharton. They used to have a reputation as a school that was friendly to older applicants, and their average amount of work experience was always among the highest. But starting about two years ago, they changed their policy, and have in fact stated in numerous chats that they have been trying to attract and admit younger students. The stats for the recent classes haven't yet been published, but I believe the new numbers will show that Wharton is now admitting one of the youngest classes around.
Regarding age, the middle 80% for most of the top schools is about 26-30. If I were a betting man (and I am), I'd bet that fewer than 2% of students at the top schools are over 34. Matt and I are both older applicants, and I definitely had a feeling that age was a substantial factor at some schools (Wharton included).
Which brings is to the important question, "what effect will it have?" Others have pointed out that her experience might make her age a non-issue; I actually disagree. I believe her age and experience will raise the question of why she needs an MBA. As I mentioned above, I believe that fewer than 2% of admitted students will be her age or older, and of those 2%, I believe that the vast majority are either from the military, or have a JD or MD. People with those experiences have a natural explanation for why they are looking to get an MBA 10-12 years out of college; they spent 4-6 years focused on something else. I think she's going to have a tough time answering why she needs an MBA rather than an executive MBA (she's an associate director at a huge company after all).
So, the real question isn't age, it's what she's done with her time and how an MBA will help someone with her experience. I think that's going to be her toughest task. I think she must have a really compelling reason why she needs an MBA, and I think she needs to describe her goals really really clearly. I think she needs to state precisely what she wants to do after getting an MBA, and how an MBA will help her reach this goal. It's not impossible, and the rest of her profile looks really impressive. I think she needs to rock the GMAT to show that she is capable of doing well academically (she's been out of school for a long time), and she needs to execute her applications properly.