Sebastian from the German Inworld Advertising Network sends in a tip about Future Ad Park (SL URL) they have set up "to demonstrate behavioral targeting capabilities". Their blog post explains: "Depending on the interest-profile of an avatar, ads are replaced immediately on billboards to deliver a personalized and relevant advertisement. The interest-profile is not only determined on the basis of where an avatar sojourns, but also combined with inquiries-data to make a prediction what he is really interested in."
Second Life is probably the closest we are to the Minority Report kind of billboards that address you by name. I've already posted about SL billboards that look for keywords in the user chatter and display appropriate ads. You can also mine other user data for targeting purposes -- name, of course, age of account (this is already being done by in-world businesses), favorites, and perhaps clothing and attachments the avatar is wearing.
This also explains why I'm posting so much about Second Life and in-game advertising: I think these environments are the testing ground for the things to come in real life.
On a related note, Austin American-Statesman interviews Joel Greenberg, a former senior planner at GSD&M (partner of MIT C3) and now VP of marketing innovation at Electric Sheep, a company behind much of the corporate presence in SL. In the interview, Joel describes what a good SL ad network could look like:
"What we are going to do is, we are going to give ad units for free. Give ad units to people to put wherever they want, and we are going to share their ad revenue with them. So it could be a poster on a wall, [...] maybe a billboard outside, maybe a button somewhere. It may be a coaster on a wall. It may be sandwich boards on their body [...]. And people will be able to place ads in the network. The advertisers will be able to choose their criteria and where they want to place it. And the publishers will be able to say there are the things I'm accepting. Just like in a regular ad network.
We will allow anyone to be a publisher, whether they are a ("Second Life") landowner, or a store owner or just an avatar in-world who doesn't own land, they can still be a publisher. They can wear it. Maybe they want to put it on their hat; they can hold it. "
Ad Network to Place Billboards in Second Life
Contextual Advertising in Second Life
MetaAdverse, In-Game Advertising Agency