backup services research

I googled around, especially with site:news.ycombinator.com for backup recommendations. Here are notes on the top hits.

tarsnap

by prolific HN member; focus on encryption and deduplication
awkward setup of encryption keys
$0.30/GB/month, not including transfer fees
automatic deduplication of identical files "across time and space"
no automatic deletion of old backups (will get expensive fast!)
only prepaid billing, with a few days warning when you run low
after 7 days of negative balance, ACCOUNT DELETED AUTOMATICALLY
commandline API that's like "tar" but automatically rsynced; "no need to worry about versioning"
push based (you have to run cron on every machine)
no real WEB UI, no email notifications on failure or stale backups

"backend to rsync", been around for 12 years
special pricing: $0.10/GB/month; requires $60 prepay: http://www.rsync.net/products/git-annex-pricing.html
otherwise $.30/GB/month, with free xfer and 7 daily snapshots.
They charge for max quota, not usage; but you can instantly modify quota via admin panel.
use any rsync compatible tool (eg rsync; duplicity; rdiff-backup; rbackup; etc...)
like tarsnap:
- push-based, requiring you run cron and maintain scripts
- no real Web UI; no email notifications of failures
cheaper and not prepaid; seems like a better option than Tarsnap

very popular desktop app for cloud backups
Java based, so works on Linux, OSX, Windows
big java APP (requires 512MB RAM for service)
web management UI + monitoring, email notifications
Requires GUI management APP, but can run backup service in headless mode ("unsupported")
biz pricing: $10/month/server or $0.32/GB/month;

Strongspace rsync backend with snapshots; $7.50/month for 60GB; free ExpandDrive license. Mac backup app.
Backblaze - $5/month mac/pc backup app; folder based (kind of like Dropbox)

like rsync but with deduplication of data across backups
Duplicity is a wrapper on rdiff-backup with encryption support
support cleaning up old versions:
supports de-duplication; incremental backups; statistics; deleting old snapshots
rBackup is a wrapper on rdiff-backup with extra features (daily/weekly..)
bup - exciting git-like backup tool

Like Proxmox or Freepbx - a hosted web UI and packages on top of backup scripts.
tons of features (daily/monthly, email notifications)
pull-based (connects to all the servers you specify via SSH)
supposed to work really well...