According to several sources, new MacBook models seem to fly out of shelves, and especially the entry-level one. The large stocks initially provided by Apple to support the official launch of the product melted as ice-cream in the sun. As an example, one could not find a MacBook on Saturday in Paris among all resellers we called.
So, for many users the lack of FireWire does not seem to have been a real "must have" factor for defining which model to purchase. Shipping info on the Apple Store remains identical, and all MacBook models are available.
[translation by Linathael]