Making a download only laptop I can understand; the Macbook Air is designed to be portable and slimline while also having good battery life, so adding an optical drive doesn't make sense.
Apple's reasoning behind getting rid of the optical drive on the new Mac Mini is a tad more dubious.
So, why did Apple do it? An Apple employee who worked on the development of the Mac Mini told me he no longer used disks, he even went so far as to suggest that nobody really used disks anymore...which is odd.
I for one still use disks from time to time; to add music to my computer, to watch DVDs (of which I have hundreds) and, crucially, to recover my system should everything go hideously wrong. I'm fairly sure I'm not in the minority and there are many people who still rely heavily on disks to use their computer.
There's no sense, for the user, in not having an optical drive on a desktop; they don't need to be super-small nor do they don't have battery life to worry about.
I can't help but feel that the real reason Apple got rid of the optical drive is to make more money. If you wanted to buy a film, TV series or music album on the new Mac Mini, the only real option you would have is to download it from (Apple would hope) the iTunes store.
Want to buy a new game or maybe a new piece of software? Head to the Mac App Store. Every time you do, Apple takes a cut.
I've never been a fan of the 'closed ecosystem' that Apple champions and this latest move is wholeheartedly depressing.