The press shots come from Telus, although there isn't much new to see in the pics. The only thing we would note is the UI change of the folder icon in Android 4.4 which is now a flat gray circle with more icons easily visible. The report also mentions that the Nexus 5 will be coming to carriers in Canada, but again no specifics there.
As far as U.S. availability, Jeff Jarvis confirmed yesterday on This Week in Google that the Best Buy display we saw is indeed for the Nexus 5. Additionally, he said that he talked to a manager at Best Buy who apparently said that there would not be the same supply issues that we saw with the Nexus 4. It seems that Google has plenty of stock, and will be launching the device in a number of retail stores, possibly on multiple carriers in the U.S. (we'd guess T-Mobile and AT&T, but we wouldn't expect Sprint at first or Verizon ever.)