Where are the Airport Express base stations?

Today it is practically impossible to put a hand on an Airport Express base station, whether at retailers, or online at the Apple Store where delivery times of one week are quoted.
This rupture of stock seems to coincide with the update of the Apple TV that brought the Airtunes function.
Apple may have created this shortage so that alternative products get pushed, or perhaps is preparing to update the Airport Express to support of 802.11n.