updated 03:05 pm EDT, Tue June 21, 2011
Lion may not have ready-made direct install
Apple chief Steve Jobs in a reported message to a Mac user claimed that Mac OS X Lion might need a Snow Leopard disc for a clean install. On those systems that don't ship with Lion media, he said a user can "can clean install Snow Leopaard [sic] first." He didn't explicitly rule out the option of starting from scratch with Lion for the MacRumors reader but implied it might not always be supported.
The requirement for Snow Leopard may not be absolute. Apple's official volume install support effectively involves downloading an installer much like those from earlier OS versions. Concerns exist that it might not be bootable, although it works with NetInstall and NetRestore and should theoretically work for fresh installs.
Jobs' e-mail is believed to be authentic.
Microsoft also offers Windows 7 as a download. The OS is bootable but requires its own special instructions to work.