In the comments section of my post about the Wacom Intuos4, I noticed an interesting comment from brushing engineer Jerry Harris:
If you are holding out on that CS4 upgrade, this tablet might entice you to reconsider. The Photoshop code that interacts with tablets had a great deal of elbow grease applied to it. The result is improved quality at the beginning and end of strokes, as well as improved response to pressure. PS now preserves pressure beyond 8-bit throughout the painting code, whereas before CS4, only 256 levels (8-bits) made its way to this code. This should be more evident when working in 16-bit layers where subtle buildup can occur in the buffers used during painting.
I need to add this point to the list of small-but-important enhancements listed in “CS4: Sweating the Details.”