(Not plugging or anything, dropbox would have done the exact same thing if I had the space for it)
For the application itself, pretty much identical to dropbox I believe. I haven't really used it since I uploaded.
I'd be an active Google Drive user, however the app kept crashing on my macbook, so I had to give up. I even spent a few days troubleshooting it with Google support to no avail.
So long as the copy.com program doesn't crash on me, this will be my online storage of choice for the foreseeable future.