As expected,has released on a USB thumb drive via their online store. The $69 thumb drive ships in 1-3 business days and requires 7GB of available storage space. One caveat for users that install OS X Lion via this thumb drive, rather than for $29.99 from the App Store, is that re-installs will need to be conducted via the thumb drive; the internet-based Lion recovery system will not function.
When you install OS X Lion using the USB thumb drive, you will not be able to reinstall OS X Lion from Lion Recovery. You will need to use the USB thumb drive to reinstall OS X Lion.
The USB thumb drive is currently available on Apple’s online store across the globe and will shortly make its way to physical stores as well. OS X Lion brings over 250 new features to the Mac including system-wide multi-touch gestures, Launchpad, Mission Control, and -like mail client, native full-screen application views, an improved Safari web browser with Reading List, automatic file saving, and AirDrop file transfers.