I... think this is usually unwise. If you attempt to appeal to everyone, you appeal to no one. I personally think one of my advantages when I ran prgmr.com was a consistent brand? At the very least, it was very recognizable. (I don't run it anymore, and I'm not claiming to have done a great job when I did. But I can point out several mistakes I made where I would have gotten... big at least by my standards if I had zigged rather than zagged. I think I did a memorable, if not a good job at branding, and "just get my name right" is... well, it's halfway there.)
Personally, I think that if you want to appeal to different markets, you should use a different brand with a different customer-facing layer, even if in the bowels, the product is produced on the same equipment.
>This is a case where tracking can actually be seen in a positive light
I'm not sure? I mean, I think that the connection between the advertiser/brand values is important, and you destroy some of that if you tailor your advertising to the consumer... if different people get different views of the same brand, well, it's really different brands.
(Also, the decision to track/not track is a brand value decision in and of itself- a rather big one, if you can credibly communicate that to your customers.)