Eh, I doubt Apple will do that. So far their playbook seems to be make all computers as insanely thin as possible while maintaining or improving performance (SSDs, no optical drives, integrated batteries, etc...). They then expect you to buy an iOS device if you want a tablet or smaller device.
The key to this whole plan is iCloud. And iCloud is basically at the same stage as iTunes when the first iPod came out. It can sync your music and that is about it. Expect Siri and iCloud to start talking to each other in the future at the very least.
Essentially, Apple is probably building a computer presence that isn't limited by a physical device that would require a laptop tablet. Yeah, they're not there yet and this does give the competitors time (iCloud is still pretty rough when it comes to anything beyond basic sync).