What you may be missing is the comment about the fact that the new flash drive with DW5 only boots into Tiger, Leopard and Snow Leopard, while users of the subsequent OS X versions need to boot from the Recovery partition on their Macs, and then use Terminal to launch DiskWarrior from the flash drive.
From Alsoft's DiskWarrior 5
System Requirements page:
The DiskWarrior Recovery flash drive ships with the ability to start up any Intel Mac that originally came with OS X 10.4, 10.5 or 10.6 installed. If you have a newer Intel Mac, you can use the included DiskWarrior Recovery Maker to update the DiskWarrior Recovery flash drive to start up your newer Mac.[emphasis added]
The manual that comes on the DW5 flash drive says the following:
"This utility application will create a DiskWarrior Recovery Disk by copying the contents of an OS X Recovery disk and a serialized DiskWarrior application to a suitable flash drive. Once completed, you will be able to start up the computer from the DiskWarrior Recovery disk and run DiskWarrior. It is recommended that you do this for both maintenance and emergencies."
The "suitable flash drive", it goes on to say, will be erased. So I don't think you would want to do this with the original flash drive on which DiskWarrior ships. But the newly created recovery disk can itself be updated by the the Recovery Maker utility so you would only need this one newly created flash drive or disc through future System versions or even future versions of DiskWarrior.
