Horrible from a corporate standpoint, maybe bearable from a individual standpoint.
Here are the main reasons for a backup:
1) Malware
2) Hardware failure
I haven't looked into online, "cloud", backups, but do they offer any kind of versioning, or multiple backups? If you get (1), how do you know when the last clean backup was?
If 2 happens, do you have a means to download an entire backup and image it to disk? Or the original CDs to restore the operating system and then restore your personal files from the online backup?
I don't like them because they are slow, depend on your internet connection and the connection all the way to the company, and they depend on whatever company staying in business, not changing their TOS, etc.
Here's my backup setup on my computers with critical files:
1) Mirrored HDs (two hard disks with exactly the same contents)
2) An NFS (network file server) on my LAN for personal and work files, system settings, etc. Sync'd to latest revision daily.
3) Weekly full backups of those file for versioning to the same server, but seperate drive.
4) Drivers and OS images are also on this server. For my laptops, I make system images whenever I feel like it (before traveling, etc.).
5) Server and all important computers are on UPSs.
And I'm covered. But this is a somewhat more technical approach.
You can get nearly the same safety just by making weekly full backups to an external drive. It will be much faster and Windows 7 has a decent backup service, finally. There's also Cobian backup which I like as well.
The only online service I've had experience with is Carbonite. Overpriced, if you ask me. For the price of one year of that, $60, you can get a 250GB external drive, backup everything a few times over, and it will last a couple years on average. I'd rather take my chances with a single external hard disk, and just replace it when it fails.