Its not really fair to simply call the Think chair a follow on to the Herman Miller Aeron. Yes, you can get it in a mesh back, and yes it follows the seat/back frame with suspension in place of padding model, but its doing a number of other things in a unique way. Plus its designer Glen Oliver Low has always been one of my favorite contract furnishing designers having done a bunch of great work for Vitra in the past.
Lets dig into the Think chair a bit.
• It seems we always start with looking at the seat back so why should this be any different. Yes, they have gone to a mesh back for this chair but in this case the mesh is supported by a series of "tendons" which allow the amount of support offered over the range of the backrest to differ. More support at the lumbar region, more give at the shoulders. The Think chair can also be ordered with a pad, a thin pad, still supported by the mesh and tendons underneath, but a more conventional look.
• The seat has a thin pad supported by heavier tendons. Seat depth adjustment is done by sliding the seat pad forward and back - nothing wrong with that and nothing revolutionary either.
• Arms are adjustable in the vertical, slide forward and back, and can rotate out (although there is no rotate in to support your elbows?). There is also a unique feature where by the arm pads will slide back on their own when you move tight to your desktop for close work.
• Perhaps the most interesting part of the Think chair is the undercarriage. Rather than the sets of coiled springs used by most chairs to control recline and seat tilt resistance the Think has a torsion frame fabricated from what I am guessing is some sort of spring steel. The twisting of this member is what supplies the resistance, and the support of the seat and back, doing two jobs at once. Its certainly unique and I'm eager for some first hand experience with this device.
As usual, a tremendous amount of info available at the Steelcase site, and many vendors offering the chair.