I spoke to representatives at Nimble to learn why this is important news to the Microsoft channel. Velosio is the result of the merge in December 2017 of Socius and SBS Group -- two of Microsoft's medium-sized U.S. resellers.
Nimble is a CRM product which is less expensive ($9-$19 per user/mo. for annual subscriptions) and less complex than Microsoft Dynamics 365 (formerly Dynamics CRM) and Salesforce. Marketed as "Simple CRM for Office," Nimble is targeted to small and medium-sized businesses who are currently using spreadsheets to track their contacts and who have not yet adopted a CRM. Nimble was founded by Jon Ferrara who was the founder of Goldmine, an early CRM for the PC released in 1990.
Although Nimble can run on its own, the product is integrated with Office 365, Google G Suite, and with popular browsers. For instance, you can download the extension for Nimble Contacts to Microsoft's Edge browser. Therefore, Nimble is cultivating the Microsoft reseller channel such as Velosio to offer their product as an alternative to Dynamics 365 when customers' contact needs are simple, and as a complement to Office 365.
Microsoft has offered contact management in Office for many years in several iterations, such as Business Contact Manager for Outlook in 2013 and its successor Outlook Customer Manager in 2016, but I have not seen wide adoption of these products among my customers (which tend to be larger enterprises).
Selling third party products through the Microsoft reseller channel is not news, but Microsoft's greater openness to third party software, even products that compete directly with Microsoft offerings, is part of a recent trend to openness. Microsoft is promoting third party products through its online marketplaces for Azure, Office and Dynamics. If they are successful in driving customers to these marketplaces it will create success not only for Microsoft but for third party vendors like Nimble and resellers like Velosio.