whats noobs
The current design isn't yet 3 years old. The previous, non-unibody design stayed with the powerbook and macbook pros, nearly unchanged, for 7 years. Yeah, that's right, 7 years.
Machining a laptop out of a solid chunk of aluminum requires very expensive equipment, and doing it on a large scale even more so, I can't see Apple who just spent a few million dollars(probably in the hundreds) in R&D for the new process would switch to a "new and thinner design". The machine and R&D don't pay for themselves.
Think about it, it is their Pro laptops, making it thinner would make Apple have to compromise even more hardware wise, which could turn a lot of potential buyers off, it makes no business sense for them to reduce the power of their laptops in exchange for a thinner design, just when they gave us the most powerful macbook pro's to date.
I don't see any new MBP's until early 2012 when Ivy Bridge is out, and I don't believe it won't be much more than a spec bump.
Apple will use the same exact "very expensive machining equipment" that you are talking about, to create the Late 2011 MacBook Pro as well as every other laptop they make out of a solid aluminum block.
All they do is program the "very expensive machining equipment" with a different CAD (Computer-aided design) file.
Simple as that.
There is NO need to invest in anymore new machinery.
Now we have a MacBook Pro
* That is 1/10 of an inch thinner
* Possibly 0.5lb lighter
* And no CD/DVD drive