How secure is google chrome's saved passwords?

Is Chrome is the only application that can decrypt it's saved passwords?

No. There is a least one program that I know of that will display the passwords.

WebBrowserPassView by Nirsoft:

WebBrowserPassView is a password recovery tool that reveals the passwords stored by the following Web browsers: Internet Explorer (Version 4.0 - 11.0), Mozilla Firefox (All Versions), Google Chrome, Safari, and Opera. This tool can be used to recover your lost/forgotten password of any Website, including popular Web sites, like Facebook, Yahoo, Google, and GMail, as long as the password is stored by your Web Browser.

There are probably others.