For a variety of reasons, I've switched to Arq/Amazon Glacier instead of Crashplan. Check it out: http://www.haystacksoftware.com/arq/
My problem is with Arq/Amazon is cost. It is not bad if you have a small amount of data. My primary machine is 1.6TB... so at the current cost of $0.01/GB that single machine would cost $16/month.
I currently have 8 machines being backed up (sometimes I have 9). My total data on Crashplan is 3.385 TB so I would be paying about $34/month. By contrast... my total cost for Crashplan+ is about $6/month (under a buck per computer). Next time I renew (~2.8 years from now)... my costs (at current rates) will increase to $9/month... or a tad over a buck a computer).
It is really hard to beat that pricing.
/Jim