If you choose to moderate all ad listings, then yes you will need to manually approve the ad from the WordPress admin dashboard, however you also have the option to publish ads automatically if you prefer, so manual approval is not required.
The current version of
ClassiPress v3.1 RC1 has only been out since the end of June, so if you're waiting for the next stable version of the theme (i.e. bugs resolved) then you can wait for the proper v3.1 release which will be released as indicated in the blog post.