The specific words you choose to use on your LP's are incredibly important. I just finished watching this one:
[ame="http://www.youtube.com/watch?v=LjQM8PzCEY0"]YouTube - Broadcast Yourself.[/ame]
For example the idea that language is a way of negotiating relationships. The different ways that you can represent the same idea to your customers adjusts their perception of the relationship between them and the content you are providing.
You are doing two things:
Conveying content and negotiating a relationship.
Let's take an example of selling Acai Berries
"Buy Acai Berries now and lose that weight"
"Wouldn't it be great to lose weight without dieting? Acai berries can help"
We are taking two totally different attitudes and negotiating two totally different forms of relationships here. I am not saying either one will work better or worse, but they are certainly different strategies that will probably appeal to different people.
The logical extension of this is to match LP's and Ads by their language.
Make an ad where the text is a direct command, and then link it to an LP that contains direct and simple information on how to purchase. "BUY NOW!"
Make an ad where the text is more informative/polite request and then link it to an LP that contains more polite language "Don't you want to start losing weight?" with implied commands.
Or mix it up, go from an informative/polite ad to a hard sell page, and see the results.
With my preliminary testing (in a different niche, not acai) I am finding that different people respond to different types of influence and that in general people who click on a soft sell ad wont convert on a hard sell lp, nor vice versa.