I've been using two network backup solutions for a while now. I signed up for Mozy for sensitive stuff since they allow me to manage my own encryption key and I use Carbonite for things like photos and videos since they do not allow me to choose my own key so therefore, they have access to everything that is backed up.
In a nutshell - Mozy is faster and has a more comprehensive client that provides detailed information about the backup status. Carbonite is integrated into Explorer and doesn't provide much info on backup state and status. Until today I'd been paying $9.95/mo for Mozy to backup 60GB from multiple machines and $49.95/year with Carbonite for unlimited backups. I do have to say that Mozy is quite a bit faster than Carbonite.
Well everything changed today when I got an e-mail from Mozy saying that they had introduced Mozy Unlimited Backup - $4.95/Month! The only difference between Mozy Unlimited and Mozy Plus, apart from the obvious 60GB limit for plus, is that you need a Mozy Unlimited subscription for each computer.
I use a server to perform my network backups (I backup from my individual machines to the server) so in my case it was a no-brainer to switch to Mozy. I highly recommend that you check them out. With the quantity of data that we are currently creating (thing media - photos, video, etc) CDs and DVDs often don't provide enough storage. The only good options, in my opinion, are backing up to hard drives and network backups. I do both.
