I installed SpiderOak on my Mac when the Dropbox security failures came to light a couple weeks ago. SpiderOak is just plain confusing and hard to use. I think I setup a folder to sync but with all of the options and "features" it has, I really don't know what is being synced or not. I'm a software developer by trade, and if I find it this confusing, I would definitely not recommend it to regular people. I'm going to give Live Mesh a shot and see how it works.

How is it better than Dropbox?

(This is not a snarky remark, I am really interested! How long have you used it? For what?)