Specialized processing hardware != general-use CPU. Face tracking and image stabilization in dirt-cheap cameras is a good example, as is hardware video decoders or graphics cards. If a market emerges, specialized hardware will be built, and it'll be embeddable in just about anything.
Face tracking is a remarkable well solved problem these days.
I have only a vague understanding of the math behind how it works, yet I'm very successfully using it in an art project I'm playing with. An afternoon's Googling found me the OpenCV plugins for Processing and some face detection examples, and I've got a prototype that really disturbs my girlfriend - I call it "Death Ray" for extra creepiness factor - but I've got a infra-red capable camera mounted on a pair of servos to steer it, and another pair of servos aiming a low power laser. An Ardunio driving the servos and switching that laser, with Processing just "magically" calling OpenCV for face detection in the video stream - _all_ the "heavy lifting" has been done for me - viva le open source!
 The thing that _really_ creeps the girl out is when I sit it all on top of the TV, and have it find faces watching the tv and paint "predator style aiming dots" onto peoples foreheads...