I have a few blog posts that get some Google love. They are recommendation or review type posts that are out of date as the restaurant is no longer open or that band isn't playing anymore at said location. Can I go in and edit these post with fresh content and update the published date in Wordpress without hurting my listing? I wouldn't be changing the url of course just updating the content. Thanks!
Yes this is fine and recommended as the purpose of search engines is to show current/up-to-date info to users. As you said you wouldn't be changing the URL you'll be fine. If you do change a URL just 301 the old url to the new one.
Yes.. In some cases you need to change the URL too... But in this case just don't forget to do a 301 redirection!!! This is a good strategy by the way, as it's important to keep your visitors up to date with the information!