Some people think the engine is ready for Flash player 10, if it works after you replace its rendering code with drawTriangles() call. In this sense Sandy is certainly ready for FP10, as seen in this little demo below:
You can see Sandy’s good old FP9-compatible BitmapMaterial on the left plane along with its hacked FP10 version on the right one. There wasn’t much effort involved in this, check out source for yourself.
So ok, you can immediately create content targeting FP10 with Sandy. But does it make it truly ready for FP10? I don’t think so, there is just so much more code asking for attention than texture mapping alone…
Cool chess texture was stolen from Icons Land.

Very cool. Although in my tests the FP10 version didn’t look as good as the old method. The image would seem to jitter while in motion until it came to a stop.
That may be because I did not pass smoothing parameter to beginBitmapFill() call, or else I need to see it. Link?
Both are looking good to me in FP10.
What kind of code do you believe needs attention to be up to par with FP10?
Do not mind other materials/attributes but, at least, we need to change all arrays to typed vectors, and then optimize data flow a bit (as you see in this example, some things are no longer needed, and other things are not directly accessible).