Popped Out Viewer option is not available in beta but will be available for the general release.
Compare (variance) is not available in beta but will be available for the general release.
When opening project in the beta version versus the legacy version, the landing page of Views will state that you do not have any saved views, even though you may have saved views from the legacy version of Assemble. Click the blue Show Legacy Views link to view your pre-defined views, and then save them in the beta version.
New projects published after the release of beta can be synced. However, saved views will not be accessible via the Add-in. Choosing to Sync from a view will provide the option to sync the default Model Inventory only. Custom views will not be available for the beta.