I don't even use launchpad... i have a mac from before they switched the buttons and i took the button off my dock.
I never said you had to use it, my reply was in response to how Launchpad and Windows 8's Metro UI are the same. However I agree with you that when I use Lion, Launchpad is nowhere to be found on that machine.
I didn't see how you can delete it. Even if you bring up the normal desktop, when you click "Start" you don't get the popup but get Metro back. I must admit that I found the preview so buggy that I ended up deleting it after a few minutes.
Visually, I'll admit that Metro is nothing like Lanchpad, but functionally they serve the same purpose -- basically a touchscreen approach to starting apps.
You can do a search online to find out how to do it. If you were looking for an official option to disable the UI then you won't find that. Look at the following link for an external solution.
http://winaero.com/download.php?view.15
W8 is still in the works, it needs a lot more massaging however with each incremental change it seems to be getting better, I just wish I had a touch-capable machine to test it further.
However I still don't see how you can compare Metro to Launchpad in that manner, that's like saying a horse driven carriage is the same thing as a modern automobile because they both need external power to drive 4 wheels.
Metro is significantly more advanced than Launchpad, they're nothing alike. First Launchpad is like the OS X dock in that it only serves to launch apps but in a grid instead of a row. Metro's tile interface allows for much more information to be displayed, can be customized unlike Launchpad, can display realtime information for RSS feeds, weather reports, etc. just to name a few.
Metro is not without its faults though, first if I were forced to use either with a traditional keyboard and mouse (because I don't have a touch interface), Metro can be very annoying as it's designed to take advantage of touch screens. It's been suggested to Microsoft that Metro should only be enabled by default only if the hardware has touch-capable devices being used.