updated 11:43 am EDT, Wed July 18, 2012
Only some carriers currently supported
Apple has upgraded its online store with the ability to get order status notifications via text message. The option is available during the checkout stage of any order, and should send out an SMS message any time shipment and/or pickup status changes. "The number of messages you’ll receive will vary depending on the orders you placed," Apple adds. Texts are restricted to the hours between 8AM and 9PM in a person's timezone.
Only some carriers are supported for notifications. The full list includes Alltel, AT&T, Boost, Cricket, Sprint/Nextel, T-Mobile, US Cellular, Verizon, and Virgin Mobile USA. Apple added text messages after pulling the store down briefly overnight; such outages are almost always related to making updates to the website, whether for feature improvements or new products.