I played a bit with the display 950 (mine still hasn't come in from B&H) and the stylus point on the new one appears to be more blunt than the stylus that came with the 900. I'd suggest getting your hands on a PDA stylus with a more tapered point and see how that works out.
I didn't test out annotation, but the 900 wasn't so great for writing either, but that might have also been because of the added touch layer. At home I have this stylus/pen combo that I used for my 900 before I sold it and will probably use it for the 950 when it arrives:
http://www.stylisource.com/detail.asp?product_ID=t1041. That site has other types as well.