Does the new iPad support higher resolution tapping, or just more pixels for display. Stylii and the existing iPad feel like writing with a big marker on a big index card. Will the new iPad feel more like pen-and-paper when using a stylus?
I practice, I can't tell any difference at all between the two models for most finger gestures on non-drawing apps.
Two things make this measurement hard - we don't get to see the raw pressure points and the unsmoothed and smoothed multitouch input. The end result of touch is highly processed which could easily hide changes in the detection grid / chip that does the processing / algorithms or tuning to make one iPad feel like the others.
The other is that our fingers cover the area we are selecting and for fine adjustments, you don't have to actually move your finger - just roll it to change the contact area of your deformed finger pad area that is either in direct contact or close proximity to the glass surface.
Once I learned to pivot and wiggle my fingers in place rather than try to slide it for fine adjustments - my precision (and feel of being able to control the precision) jumped immensely.
On the other hand - drawing with a stylus or deft and rapid strokes with a finger in a good drawing program makes the end feel on a retina iPad much better than before. I don't know if this is mental or real, but getting a finer line out of the same repeated gestures is incredible and makes the new hardware feel much more like pen or pencil and paper to me. I can't tell if it's the CPU/GPU or hardware or illusion, but the feel is quite real after a short adjustment period.
Only if you file your fingers down to double precision ;)
But seriously, no, the actual capacative touch screen layer is unchanged, because the thing that is needs to interact with (your finger) remains unchanged.
To take a simple drawing application as an example, drawing a spiral will receive input from your fingers in the same way as on an iPad or iPad 2. It takes the locations of your touch and tries to take an average of the "centre" of your touch point and this will produce the same results, although when translated into your drawing the enhanced resolution allows the touch algorithm to smooth out the centre area to a slightly more accurate level which may result in a more accurate looking drawing, but it's not due to any resolution changes in the touch sensitive layer, just a more accurate rendering of the existing input.