Cloud migration specialist Binary Tree is no stranger to Microsoft’s BPOS SaaS productivity platform, with a stated focus of moving customers from legacy messaging systems to Exchange Online. And now Binary Tree has signed a strategic partnership for Microsoft to use their software tools when migrating customers from the IBM Lotus Notes to BPOS. Here’s the story.

Binary Tree first caught The VAR Guy’s all-seeing eye in October 2010 when it announced it was abandoning its membership in the Google partner program to focus exclusively on Microsoft BPOS migrations. And with this partnership, it looks like they’re getting even further into bed with Redmond.

Basically, the deal means that Microsoft will leverage the Binary Tree migration software on their hosted cloud infrastructure, enabling rapid content migration. And if a customer wants Lotus Notes to coexist with their BPOS deployment, Binary Tree tools can handle that too.

Having a migration specialist on their team can only help BPOS — soon to be Microsoft Office 365 — in the marketplace. There are plenty of Google migration partners, too, but none that The VAR Guy is aware of stopped selling BPOS to focus on Google Apps exclusively. And, of course, this announcement represents another shot fired in the never-ending Microsoft vs. Lotus war.

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