the guys at my local brewshop told me to add blueberries to the primary (for a blueberry wiezenbier). I did this when the fermentation had slowed to the point at which I would normally rack to a secondary.
It seems to me that no matter what, the sugars in your fruit are going to ferment again, at least slightly, because you are adding fermentable sugars to wort with active yeast. This will carry off a little bit of aroma, but the problem most people talk about would only really happen (i think) if you started your primary with fruit from the beginning. I added the fruit to my primary because it is a lot larger than my secondary (6.5 gal carboy as opposed to 5 gal carboy), and I appreciate not having to worry about my airlock blowing off a secondary fermenter due to a second ferment from fruit.
the blueberry wiezenbier tasted great upon bottling, but I will have to let you know how it turns out, as it was just bottled a few days ago.
hope that helps.