As I look back over the evolution of blogs, community, and commenting/engagement on media sites, I have a mixed feeling about anonymity.
On one hand the ability to use a pseudonym has encouraged participation where it might not happen, but on the other it has enabled a raucous and at times a very mean spirited experience. Just take a look at the comment stream on any story on SFGate and you will see this in action, the result being that the comments end up not being informing and additive to the original story but rather a sideshow of people shouting at each other.
When a service is Facebook Connect enabled the login process for the subset of people that want to use it strips away pseudonyms and exposes your real name and profile information. The result is that we will end up with a two tier community model and this could be a very good thing.
Most people will be more thoughtful and, hopefully, cordial when their comments are attached to them as a person rather than the pseudonym “asshatman69”. People who are interested in civil debate and genuine participation over ranting will value services that have a growing population of Connect logins and as the pendulum shifts the result will be that the quality of the overall debate will rise as a consequence of the natural discounting of pseudonym posted comments. Real people with serious things to say will crowd out the shouters.
It also goes without saying that the ability to aggregate a stream that builds around a person rather than a site will enable new discovery capabilities.