They have been in Wal-Mart all week. No need to wait.
Hopefully this is indicative of Google FINALLY providing updates, and opening up the App store to other developers.
Bought mine today at Best Buy. Super pumped at how it integrates my HDHomerun (HDTC-2US), a little annoyed at how many frames it drops, even with the device's transcoding turned on. Ordered a USB OTG adapter and a USB ethernet adapter, hopefully either that or better software solves that problem. My Nexus 7 plays the TV streams just fine.
if only they would start selling them international too. I hope Razor sells theirs in Australia
Bought 2 more as gifts at Best Buy. They are already selling them, though they didn't have any gamepads yet.
Walmart by me had them on the Clearance table a week ago.
Best Buy will begin selling them the 25th as well. We got them in the other day in our warehouse.