You would also notice that I did not specify a device that connects via usb or firewire as a NAS - but rather that a device that handled raid internally that connected via firewire or usb - whether it be a NAS unit or a usb or firewire attached raid unit, if the raid functionality is handled internally, the OS will be oblivious to it.
Also, as you may (or may not) there are devices available that can convert a USB or Firewire storage unit (raid or not) into a NAS - for example: Apple Airport Extreme has usb ports for external drives which will now make them appear as a NAS, Linksys also has a device that does the same feature, and the Droboshare device will take a DROBO and make it accessible as if it were a NAS - basically, what I was trying to say was - whether it's a NAS device or a directly attached device - if that device handles raid internally - that functionality will be usually shielded from the OS and the OS - whether mounting the device remotely across the network via SMB, NFS, etc. or locally by firewire or USB, the storage will not magically change. The same is also true for SAN units (in case you don't know what they are, it's another technology for network storage) where these days, iSCSI is used commonly to connect to the device - the device itself handles the raid functionality and as long as the OS has iSCSI drivers, it can communicate and utilize the network storage and ignore how the drives are configured.
My goal in my post was to make sure it was clear that an external device that handles its' own raid functionality, and has a commonly used connection technology (whether ethernet/wifi, USB or Firewire), that device will be available as storage on either platform if the OS supports the appropriate connection technology.
So please, although I'll admit, I may have worded the post perhaps a bit shorter with a bit less explanation than I should have, the sarcasm in your reply is not necessarily appreciated.