I succesfuly upgrade a A500 to 4.0.3 today, but i found a problem in the screen... now when is not at 100% of brighthess, is seems like a flirk in all grey/black's colors (it's look very clear in al the background of control panel).
The "flirk" it's like what you see in CRT monitors when you not select correct refresh frecuency, or when you record with a videorecorder an old TV. That is the bad effect that i found in all system (games/video/gallery/etc).
Videos now are all HW decoded, and are completly smooth, all system are more smooth, but characters/font's are lees clear/sharpner because of GPU render.