Sorry this is a little late - but I've just today read this from Brighton blogger Neil Harding. He does the maths, and reckons that the Green Party could romp home with 21 councillors in the 2011 local election, if all parties' votes are in line with the swing seen during the July Goldsmid by-election.
I think Neil could be right. At every local election we seem to increase our numbers about two-fold. Voters do seem to like what they see with the Greens - a little familiarity is often all it takes to persuade people that we are about creating a fair society, and stronger neighbourhoods, as much as we're about the protecting the environment - though obviously they are all interwoven.
We'll have to see, eh: roll on May 2011!