Both include 1TB of OneDrive for Business cloud storage per user, the Office Online lightweight and Web-based version of Office and what Microsoft describes as "core" Excel BI (business intelligence) features.
However, unlike Office 365 Business, Office ProPlus has advanced Excel BI features, as well as several email compliance, archiving and retention capabilities, and a set of IT controls.
Microsoft is also adding flexibility for customers that want to have some users on the SMB plans and some on the Enterprise plans.
Currently, Office 365 Small Business can be combined with Office 365 Small Business Premium, but not with Office 365 Midsize Business, the Office 365 Enterprise plans, or the stand-alone products, like Exchange Online. Office 365 Midsize Business can't be combined with any other plan.
However, those rigid boundaries are coming down, so a company will be able to have different users on different plans, and even add products like Visio, Project and Dynamics CRM Online to some seats.
The three new plans will launch on October 1 of this year, but Microsoft is recommending that existing customers wait to switch until their next renewal date after October 1, 2015.
In the meantime, Microsoft will raise the user cap from 25 to 300 for Small Business and Small Business Premium customers, and lower the price of the Midsize Business plan from $15 per user/month to $12.50 per user/month.
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