German site MovieReporter.net spoke to Peter Jackson recently and he confirmed that The Hobbit script is almost finished its second draft and headed before cameras next summer.
Helpfully translated by TheOneRing.net, the news is that the script's due to be finished in December or January, with shooting expected to take place in the summer of 2010. Jackson also said that the budget has yet to be calcuated, based on the script, and that the greenlight has not officially been given yet. Don't expect that to be too much of a problem at this stage, however: there's a fairly substantial chance that this film will make buckets of cash for the studios behind it.
As far as we know, The Hobbit is still due out in December 2011 with the proposed second film due in December 2012.