I don't really buy that rumor. Apple rarely to never does a six month cycle on anything and shifting the iPad to the fall means no major product to help keep the stock price nice and high.
Plus an iPad on top of the new pods means more chaos for the retail staff, which I can't see them doing.
If anything I could see them shifting the iPads to late Jan or early Feb next go around and moving the spring laptops closer to the start of their annual back to school promo
And what about production. 18 iPad models and they're starting to catch up but what about components? They have some inventory now and are desperately looking for suppliers to replace what Japan won't be able to deliver for awhile. I do believe (and hope) there will be an iP5 with the phone and the ios5 announced who knows - end June - preorders open end June, delivery starts mid-July and ios5 on the way. Remember, Apple released iPad1 and it was months before those iPads could update to ios4. They stayed with ios3.1 for quite some time.