The rumored "Brick" from Apple turns out to be the process of forming aluminum by the use of lasers and hydro-forming. The process allows the case to be made from a solid piece of aluminum or "brick", instead of castings which make for a stronger case.
"The MacBook manufacturing process up to this point has been outsourced to Chinese or Taiwanese manufacturers like Foxconn. Now Apple is in charge. The company has spent the last few years building an entirely new manufacturing process that uses lasers (w/o sharks) and jets of water to carve the MacBooks out of a brick of aluminum."
Previously we thought the "brick" referred to a new, much needed, Mac mini. If rumors hold true we will see this new MacBook in a couple weeks and maybe they will even boat about its "brick" techniques.
THis means the new MacBooks must be very thin and they needed this process to eliminate the weakness of casting aluminum.