We received a lot of feedback from the community and other developers about the Extension Manager VSIX manifest and made some changes in Beta 2. Some of the changes included:
Ofcourse, these changes will require you to update your Beta 1 manifest files. Instead of manually tweaking your XML, we've built a nifty cool VSIX Manifest Converter tool to help you move your Beta 1 manifest to Beta 2.
The tool is attached to this blog post. To use it, just run the exe in the directory where your VSIX or extension.vsixmanifest file is. The tool will automatically convert the manifest. If you have a VSIX, it'll crack open the VSIX, update the manifest and repackage your VSIX.