The NY Times has published a column in its Bits Blog that summarizes the evolution of Facebook's Beacon advertising program.
I think that it is more revealing than focusing on the backlash or petitions to actually examine the program itself, along with the supposed improvements made by Facebook along the way. The column does a good job at pointing out the small tweaks that seem to address raised concerns, while essentially presenting the same thing again, but with more labels.
It becomes the user's responsibility to be ever watchful for Facebook's unorthodox info harvesting. A better approach would have been a way to opt-in instead of having to constantly opt-out. There is currently no way to globally say "no thanks" and be done with it, either.
A reader comment from the site:
In the latest article in the NY Times, some ad executives remark that users are being hypocritical because they reveal so much other personal information. I think these ad executives are idiots and missing the point. Facebook users volunteer the information. They don't want to publish all the information about their lives. The availability of choice is what makes a Facebook profile fun. People can choose to reveal what they want. However, this new Beacon program creates a huge invasion of privacy because it doesn't really offer that. To have to check the box each and every time you make a purchase unduly burdens the consumer.
I won't hold my breath.
[update] Facebook is "reining in some aspects" of Beacon (nytimes.com).