From this press release I take it you cannot simply walk into an Apple store, play with the iPad mini and then buy one from store inventory. The only people walking out of Apple stores with these will be those who have ordered online and scheduled a store pickup, which means days after they ordered online. This suggests severe supply constraints.
Apple begins selling retina iPad Mini • 7:40 AM
Three weeks after Apple (AAPL) unveiled the retina iPad Mini, the tablet is available for purchase at Apple's online store. 16GB and 32GB Wi-Fi-only models are showing shipping times of 1-3 business days; other models are at 5-10 business days. The retina Mini had been expected to go on sale on Nov. 22, following a Target leak indicating as much.
Two issues that will be closely watched: 1) Supply constraints. There have been multiple reports stating early Mini supplies will be limited due to display shortages, and Tim Cook admitted on the FQ4 CC it isn't clear if Apple will be able to meet Dec. quarter demand. 2) How much the Mini's premium pricing - the device starts at $399 at a time when the Nexus 7 and Kindle Fire HDX, each of which also have high-res displays, start at $229 - will affect sales.
The iPad Air went on sale on Nov. 1. Initial reviews and activation/usage data have been positive.