According to Bloomberg’s findings, there are three job listings on Nvidia’s database that reference Apple, with the latest one appearing last week. One ad for a software engineer says that the successful applicant will "help produce the next revolutionary Apple products." The person will be "working in partnership with Apple," and write code that will "define and shape the future."
From the looks of it, Apple is preparing to switch graphics chips from AMD to Nvidia, although nothing is yet confirmed. These Nvidia GPUs will likely power the higher-end Mac machines in Apple's future lineup. The company is also rumored to be working on Thunderbolt Displays that have integrated graphics, which could also benefit from this partnership.
Currently, Apple’s more portable devices including the 13-inch MacBook Pro, the MacBook Air, and the MacBook do not feature discrete graphics options. Instead, they rely on integrated graphics chips from Intel.
Given that Apple’s major MacBook Pro announcement is scheduled for sometime in October, it's likely that the revolutionary products Nvidia will co-develop with Apple will not arrive this year. The job listings are still exciting, as it looks like Apple is ready to bring back Nvidia hardware to the Mac line.