Region, none of those pictures in your link were particularly good. The one of the bush looked most like what we get, but the photo was small enough that it's just an undifferentiated mass of green, can't tell much from it.
This is a pretty good pic:
The leaves aren't always serrated, though. Sometimes they're more like:
This time of year, the developed leaves are a matte deep green, and the brand-new ones are shiny and sometimes reddish.