New old stock
The good dealers like Colonial will clear their old inventory asap, and will discount it to do so once the new models start arriving.
However, the older models HAVE sat out in the weather for months, and small leaks may have gone undetected. The floor needs to be inspected just as if it were a 5 year old model. I'd insist on a pressure test for leaks - nothing else really reveals the little ones.
Brand new 2013's will get minimal discounts through the summer camping season. In the dead of winter you can sometimes get 20% off or just a tad more from a dealer.
One thing I do like that they've changed in the 2013 Classics is moving the batteries out of the body of the trailer and onto the front tongue. Easier access, no worries about corrosion or off-gassing inside the Airstream. Losing that bumper drawer not so good.
May I suggest you look at very gently used Airstreams? 2-4 years old. Big savings, huge in fact. You must be wary of condition, but some get put in a garage after 2 trips and are really time capsules!
Colonial has a great reputation, so if you're set on new and they have a 2012 - stand your ground for a good discount but go for it.
Happy trails, Paula
Today is a gift, that's why they call it the present.