Have you seen the LabVIEW 8.6.x Known Issues page? These pages were originally started with the LabVIEW 8.5 release. It's a great way to check and see (1) what potential issues you may have when upgrading to the latest LabVIEW version, or (2) whether or not an issue you're experiencing has been reported as a known issue before reporting it yourself.
The pages can be organized by category (ActiveX, File I/O, etc.) or by date (with the most recently-reported known issue at the bottom of the page). Also, you can subscribe to an RSS feed to receive notification whenever the Known Issues page is updated.
Make sure to submit any feedback you have on the Known Issues pages here. Also look for a new Known Issues page to be created with each yearly LabVIEW release.