I'm still using Siri and am looking forward to getting the rest of the functionality in the UK. I find it works pretty well, right up until the point when I try to demonstrate it to someone...

My 4S also has a rattle, but then so did my 4. Still feels solid to me.

I wish battery life was a bit better on wifi, with moderate use at home I find the battery only lasts 24 hours or so now. However with wifi off it goes back to more like 48+ hours.