Nobody knows. Apple likes to be very secretive. The last MBP refresh was supposed to be some major revamp according to a lot of rumors, and it turned out to be a fairly minor update, though some of the under the hood changes are pretty significant.
You can either be perpetually waiting for that next model, or you can just be satisfied with what there is now. And major revamps aren't always a good thing. The current unibody design has had a good couple of years of real world testing, and time for Apple to make some subtle tweaks here and there to fix issues that have come up. There are a lot of technicians out there who are very familiar with how to work on these systems, etc. If they overhaul the entire design, there's always a chance it will be very problematic in the beginning.
You want my advice, stop with all the grass is greener thinking and just buy something. Don't worry about what might come to pass, because who knows if it will or if it will be better. For all you know, you could get hit by a bus in 2 weeks, so you'd never get to see the revamped model, and would have denied yourself some enjoyment in your final days.
College student graduating soon. I want to take advantage of the student discount while I have it to buy a nice new macbook pro. Problem is, I hear that the line is going to go through a complete revamp in the next year. How likely is that to happen and is it worth the wait?

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