This is part five of a six-part op-ed series in which I make my predictions for Apple’s product line-up for 2012. Today we’ll look at the company’s Mac laptop line-up.

There have been rumors of a 15-inch MacBook Air. My crystal ball says it’s coming, along with a 17-inch version. In fact, the entire Mac laptop line will evole into Airs. The 11-inch and 13-inch models will be dubbed MacBook Airs, and the 15-inch and 17-inch versions will be called, simply, MacBook Pros.

All models will come in the svelte design the current Air line-up is famous for. All will ditch built-in optical drives and sport only solid state drives. Apple will expect those who want an optical drive to buy its US$79 SuperDrive. Need more storage? Apple will tout the power of Thunderbolt for that and promote Thunderbolt drives from several companies, which will finally arrive on the scene in greater numbers. The price tag on the pricey drives will drop a bit.

Apple’s future MacBook Airs and MacBook Pros will feature Intel’s next-generation Ivy Bridge processors, which are slated to arrive at some point in the first half of 2012. Though Ivy Bridge will support USB 3.0, we won’t see it on any Mac. Apple has decided the future of connectivity on its computer line is Thunderbolt, though it will continue to offer USB 2.0 ports for the foreseeable future.

Those MacBook Airs running iOS that have been rumored? Ain’t gonna happen. All Mac laptops will run OS X. Also, don’t look for Apple portables with Sir support or 3D features.

Tomorrow: Mac desktops.

— Dennis Sellers