Maybe not, but a slightly different architecture (e.g. Dropbox) would allow someone to have the cloud service but also back up the files via a second service, t

Maybe not, but a slightly different architecture (e.g. Dropbox) would allow someone to have the cloud service but also back up the files via a second service, thereby diversifying between different services to reduce the changes of a complete file loss. Evernote's model doesn't really allow for this, you have to rely on them to do it for you.