In keeping with past releases of the iPhone OS software for the iPhone and iPod touch, Apple today announced that the iPhone and iPhone 3G versions of iPhone OS 3.0 will be free for current iPhone users, and that the iPod touch version will be available for $10. Slides at the event, interestingly, depicted the iPhone as receiving a new Voice Memos application previously announced in the presentation, while the iPod touch was shown without the application;…