A year after teaming up with Apple on an enterprise partnership to push iOS devices and apps for business users, IBM is moving forward with plans to rapidly move its own employees onto Apple's platforms, MacRumors has learned.

While IBM announced in an internal memo several months ago that it was planning to purchase up to 50,000 MacBooks for employees by the end of 2015, chief information officer Jeff Smith has revealed in a new internal video released to employees yesterday that he believes IBM could actually end up purchasing 150,000-200,000 Macs annually.

"I'd like to be able to offer these to everyone that can use it. We've got to find a way to make the overall cost the same or lower than PCs to make that happen. Would you be interested in helping me do that, because you guys know these devices", and he said, "No, Jeff, we'd never do that...very secretive, we never allow anyone in. You know, we just don't do that." And I said, "Well who's your largest corporate customer?" And he said "Well, that customer has got about 25,000 MacBooks a year." And I said, "Well we could be 150-200,000." And he goes "Jeff, that's a great idea! We're gonna come here, you know, next week...you bring your whole team," and that's exactly what happened.

In the video, Smith relates a conversation he had with Apple's chief information officer Niall O'Connor about the possibility of a massive Mac deployment for IBM.

In a separate clip from the video, Smith describes a recent conversation between Tim Cook and IBM vice president Fletcher Previn in which Previn indicated the initiative could see 50–75 percent of IBM employees eventually converting to Macs from the Lenovo ThinkPads that are currently the company standard.

Apple and IBM, former rivals in the PC market, have been working increasingly closely together on both specialized enterprise-focused iOS apps and more recently on HealthKit and ResearchKit data management tools. With so many IBM employees now in line to switch to Macs for their work machines, the stage is setting up for even more collaboration going forward.

Update: Given IBM's workforce of under 400,000 employees, it appears the "200,000" figure cited by Smith could be a total replacement cycle figure rather than an annual purchase amount. Still, based on a three or four year replacement cycle, IBM would easily become Apple's largest corporate customer.