> it doesn't look like Google offers synchronization so its utility as a backup environment is quite limited.

Actually, my beef with all these services is the opposite: they rarely provide support to mount plain old drives under windows. It's always some crappy web interface or custom client that synchs stuff around which makes it non-interoperable with every other program I use that just wants to save something to the file system and know that it got to the cloud. I really don't get it - Windows supports WebDAV - what is so freakin hard about this?

I really wish they would just give me a network drive to save to and let me worry about finding some synchronization software to mirror stuff there if that turns me on.