You are absolutely right. However you comment reminds me this one from original Dropbox announcement on Hacker News:

"For a Linux user, you can already build such a system yourself quite trivially by getting an FTP account, mounting it locally with curlftpfs, and then using SVN or CVS on the mounted filesystem. From Windows or Mac, this FTP account could be accessed through built-in software."

This might be a fun experiment for a developer. But for the broad user perspective even replacing launcher is a big deal.