Today’s (Cloud) Tip… Feature Comparison of SharePoint Online in Office 365 plans
All Office 365 plans include SharePoint Online, but not all plans include the full SharePoint Online feature set. Do you have the complete matrix memorized? If so, then stop reading.
If not, check out http://technet.microsoft.com/en-us/library/jj819267.aspx. It has a full matrix of the Office 365 plans and the features of SharePoint Online included in each plan.
As a bonus, the list includes a number of SharePoint features that only exist on-premises and thus calls them out explicitly as not existing in any of the Office 365 plans. For example, note that State Service is listed in the list, but not supported in SharePoint Online.