I still don't quite see the value in online backups. I can appreciate the extra safety of "off-site," certainly, but the cost and time and hassle just don't add up for me.
I have, like a lot of people I suspect, basically three types of data on my computer:
1. Stuff I could EASILY reinstall if I lost it -- my OS, most of my apps, the stuff iCloud and iTunes Match covers.
2. Data I really wouldn't care that much if I lost it -- files I haven't looked at in years, apps I don't use anymore, old videos I downloaded from somewhere, non-essential media, outdated bookmarks, old emails and so on and so forth.
3. Data I really can't afford to lose -- in my case mostly pictures and videos I created, stuff I wrote, financial records etc.
I currently back up ALL of this, though I'm always working on pruning category 2.
I use a drive dedicated to Time Machine, and another external drive dedicated to a clone backup.
Stuff that falls into category 3, I periodically back up to DVDs and store them elsewhere.
This system of mine has, so far, made it easy to restore data on the occasion of drive failures. Within a day I'm back up and running in my experience, pretty much right where I left off.
Flickr Pro (and I'm sure other services) offers to let me upload my entire photo library for I think it's $25 a year. Combined with iTunes Match and iCloud this is the bulk of stuff I don't want to lose (or perhaps more accurately be unable to restore), so that's what, $50 a year? A decent insurance policy, and what little of category 3 is left to protect (the documents, mostly) is so small that a good thumb drive would probably handle it.
That's my view at present. I reserve the right to change my mind as technology and circumstances evolve. I do live in the Ring of Fire, after all ...