Is optical media obsolete?

With consumer-grade desktop hard disks these days offering capacities of 3TB in a single volume, and USB flash memory drives offering mimimum capacities greater a single DVD, I cannot see much of a need for CDs or DVDs any more.

For purchasing music, TV shows and movies, the offering of digital downloads has eclipsed purchases of physical media.

I haven't used DVDs for backup purposes for years, as they just do not have enough capacity. When a single shoot can easily exceed what one DVD can provide, there's little point using them.

Apart from the insufficient capacity, I don't trust the reliability of optical media; it can be easily damaged, and sometimes just doesn't work in a given drive.

I was sent a DVD recently, but my machine could not read it. I had to insert it into another machine and copy the files to a USB stick.

Additionally, some laptop/notebook computers these days do not even provide optical drives. The latest generation of the MacBook Pro (my computer of choice) no longer includes an integrated optical drive (an optional external unit can be purchased), and Apple these days prefers to supply new versions of Mac OS X via digital downloads from the Apple Store.

What optical media has in its favour is that it's cheap. If you need to send files to someone on physical media, it's cheaper to use optical media. For that reason I still keep CDs and DVDs here; I otherwise don't use them, and won't replace them when I run out (which could take years).

All of my data resides on my MacBook Pro's hard disk, but I regularly (weekly or fotnightly) back up to three external hard disks, two of which I keep here, and the third of which I keep at a geographically-diverse location. A few weeks ago I bought another external hard disk which is going to Africa with us this week (and which I'll use for keeping a separate copy of all of our images), but when we get back it will probably serve as a fourth backup drive.

So, what do others think? Has optical media outlived its usefulness?