Sprint warns it's a 'little behind' on Samsung Galaxy S III, T-Mobile staggers its launch

That delayed Canadian Galaxy S III launch may have been a harbinger of US delays to come: Sprint has let Engadget know that it's running a "little behind" on shipments. The company still hopes to get all pre-orders of the 16GB model to customers by the official June 21st release, but warns that orders might slip by one or two days. We also hope 32GB customers weren't planning their schedules around the 21st -- the higher capacity won't ship until the following week. Sprint is citing both "overwhelming demand and limited supply" as the root causes, although it hasn't quantified just how whelmed those sales are.

T-Mobile, meanwhile, is telling Galaxy S III buyers in some areas to sit tight. We've directly confirmed through a spokesperson an earlier leak from TmoNews that claimed Magenta will only focus June 21st retail sales on the "top 29 markets," most of them major cities. If you fall outside of those areas, you'll have to wait until shortly afterwards to pick one up, the provider tells us. As it stands, AT&T, US Cellular and Verizon still haven't committed to exact release dates and are currently off the hook.