The artifacts aren't that bad -- I only notice occasional banding while scrolling.
Yup... I've been using it since it arrived on nightlies and that's the only ill effect. Of course, I turned it off and haven't noticed much of a difference in speed loss either. Same with the browser. It does crash a lot with acceleration on. Hopefully, ICS is better. They are supposed to use hardware acceleration on everything including a lot of apps that you would never think of. I hope they work out the bugs though. Opera is by far the fastest browser but its rendering is kinda screwy sometimes. Nothings perfect, I guess...