if only there were as many products released as times that this exact question has been asked here.
my best guess, you'll see stuff announced at CES (january) with a release date sometime next summer.
USB took a long time to have devices come out.
USB2 took a long time to have devices come out.
look at firewire 800, it's on a lot higher percentage of the computers out there than thunderbolt is.
Go to any retailer (or their web site) compare the number of drives available with FW800 tot the total drives out there.
airplay, pretty much an easy add on to existing technology, announced last september, lots of devices announced at CES, and those announced products are still slowly trickling out into the market