I'm still using CrashPlan and still reasonably happy.
I do wish they'd get on and fix some of the important design oddities. In particular I want them to fix their local/remote detection. Assuming that every machine hosted on a public IP address is remote is lazy and daft (and it a real *pain when it comes to restore time).
Having UK storage sounds like a good idea, to avoid the hop over the pond. And I'll bet that hosted storage in the UK costs more than in the US, so it is bound to cost a bit more.
When it comes down to it, it works much better that the other online solutions I've tried. All of which either don't cope with very high overall storage levels or can't cope with massive files (>40GB virtual hard disk files).
I use it to backup the massive virtual disk images on my laptops to my server (350GB of data backed up). I also use it to backup 285GB from my server to CrashPlan Central (and also a small amount direct from my laptops to CrashPlan Central, things like the local git repos for my current projects).
I like its flexibility compared to the others I've tried.
I have never yet made use of the backup to other users feature, as my 800k upstream is just too slow to host my servers and to start swapping large amounts of data with other people.
* to restore to my laptops from the server, I have to temporarily raise the server's send bandwidth limit, as the server is treated as being remote from the laptop on the same local network because I use public IP addresses