The van for the Nets still comes from Jersey, understandably. (In either case, it may not be so easy to reach them.)
The Forest City Ratner booth was busy enough when I stopped by, but that was when the Brooklyn Steppers drummers were doing their thing. (NLG has a photo of the popular basketball hoop; AY/Nets trinkets are awarded in exchange for baskets.)
I was told the arena would open in 2011; that's a change from the last street fair I attended, the Brighton Jubilee, when I was told 2010, but I still think that 2012 is a more realistic best-case scenario.
On the other hand
Develop Don't Destroy Brooklyn was touting its October 18 Walk Don't Destroy fundraiser and reminding people that some people think Newark's new Prudential Center is a viable home for the Nets.
The Council of Brooklyn Neighborhoods offered some basketball satire.
CBN touted the UNITY plan.