Its true that they probably wont do a redesign tell next year. One thing that makes it seem more promising is the fact that the majority of Apples sales are coming from their portable devices Steve Jobs noted this recently.
If they want to grab some more market share in the PC category which is important for them to keep growing exponentially they need to keep stepping it up and separating themselves from the rest. I think one day soon they will learn how to create the I-sight right in the screen, one that hides when youre not using it. Also I wouldnt worry about where the speakers or other things will be, John Ive will come up with something amazing I'm sure.
I think the black border really defines the product as being an Apple product but eventually they will do away with all the fluff as you know apple is a contemporary minimalist company they go for sleek and sophisticated and they somehow manage to do it in smaller and smaller spaces.
One other reason why I think they will go borderless when they have the ability is because they have done so on Safari and even with the full screen feature in the OS Lion. Could you imagine looking at your picture or video as if someone is holding it up and its right in front of you instead of a frame to distract you, that would be something revolutionary! Steve I hope your reading this!