Ole Begemann reviews the Backblaze cloud-backup service:

Backblaze is the second online backup service (after CrashPlan) I have tried for a significant amount of time. Now that I have been using Backblaze for the past nine months, I believe I can make a fair evaluation of the service.

This isn’t your usual casual review. Ole covers all of Backblaze’s flaws, from the client software to issues with external drives to metadata loss to limitations when moving and restoring files. In the end, despite these problems, he’s sticking with Backblaze “for its unobtrusiveness and convenience,” but he continues to look for the perfect online backup.

(I currently use Backblaze for online backups, but for me, it’s my Worst Case Scenario solution. For “normal” backups, I use Time Machine along with nightly and weekly clone backups, rotating the weekly clone offsite.)