Zinio, if you aren't familiar, offers magazines in digital format (yes, with DRM), many of them with rich media like embedded movies right in the pages, for Mac and PC. They have quite a selection and they've been around for a few years now, but apparently their latest version (released around the dawn of time) is suffering a quirk due to Apple changing the way QuickTime renders Flash with the latest QuickTime 7.1.3 update, causing embedded rich media to misbehave.
Fortunately, they've issued a fix via email, and it goes a little something like this:
- Close the Zinio Reader, if open
- Go to the QuickTime pane in System Preferences
- In the Advanced tab, check 'Enable Flash'
This fix, by the way, is also how you enable iTunes 7 to play interactive booklets from the iTunes Store according to this Apple KB article.