I like Google+, and circles are definitely a far more natural (read: closer to real life) way of interacting with your contacts than the blanket approaches of both Facebook friends and Twitter followers. But the issue of ‘circles’ intrigues me in the context of the filter bubble.
Twitter itself is still self-moderated, I will only follow you if you tweet (at least occasionally) about something that interests me, but Google+ looks to seal off the bubbles we create for ourselves even further. Looking at the Sparks I have set up so far this seems to me to be even more filter-bubble-like.
Has Google+ just made it even harder for brands to enter the filter bubble?