paolo:
One in particular is a pixelated, sparkly screen when viewing dark (graphite) colours. It's perfect on 10.4 so not hardware. Using a Macbook Pro 2.33 C2D 17" in case anyone else has similar probs.
That makes very interesting reading, I also have Leopard and have witnessed this, I had put it down to my new Monitor (Samsung 206BW) not displaying greys/blacks very well but maybe not after reading this.
Is this a known issue on Mac Forums? - 10.5.1 hasn't fixed it so hopefully the next update will.
That aside it's a superb operating system, very pleased with it (have gone from 10.3 straight to this).