Gmail sponsored links and email marketing

It seems this is my Gmail week :)

Thinking about the latest Google announcements and their possible impact on email marketing, a question Struck me:

All best practices around the world strongly advise to use as much text as possible in email communications with clients/prospects.
One thing with Gmail is that they use the sidebar to display contextual ads based on the email content.
Now, the more text you use, the more relevant these ads will be. Should they turn out to be more relevant than your message, what is the risk the click goes to someone else (a competitor very likely)?

Here is an example of a Borders communication which is I believe a good illustration of what I just said:

Click to enlarge

I'm not very sure where I could find statistics on the subject or how to efficiently check this assumption

If you have an opinion, please feel free to comment.