Going by what I've seen over the last few years, the new 2011 models should be in the dealerships around Feb/March time.
As for being a good time to buy? If you're set on getting a bike, why wait? Prices are high at the moment for new bikes, I think it's due to rising manufacturing costs, so the prices of 2008 and even 2009 seem long gone – knock-on affect is that second hand prices are also high!
I’m in a predicament at the moment, I really want to get back onto a bike and enjoy these last few months before starting the cold winter rides, but I also am very tempted by the upcoming Ducati 848 Evo – it’s ‘only’ £2,500 over what I had planned to pay for a new Daytona 675 so is a very real prospect….