I read app release notes because I like to see what an app’s capable of doing. I’ve noticed that some apps have gotten lazy recently and just put something like “we update our app regularly”. When I see that, if I’m not actively using the app, I delete it. If I am actively using the app (I’m looking at you, Dropbox and Facebook), I try to think of other apps I could use instead (e.g. OneDrive, Google Drive, and heck, “nothing” sounds like a good Facebook replacement). See, I feel insulted that they want to just shove new code over my Internet connection onto my device when their changes aren’t even important enough to include in a text file they push to iTunes Connect. So, developers, if your release process is so agile that you release updates regularly, then track what you’re releasing and add it to the notes. Otherwise, I think your release process is crap and I’ll delete your app to keep said crap off my devices.
Update 7/6/16: The Dropbox app is currently rated 2 of 5 stars in the App Store, despite being a great sync service and listed in The App Store’s “essentials” list. Why? No release notes.