GNOME 3.10 Released

1. yes
2. yes, more or less: at my home we have four current laptops: a MacBook, an Acer, a Sony, and a HP; the Mac has a gesture (three-finger tap), the Acer has a physical third button/"mouse wheel" (it's actually a five-way clickable joystick thingy), the Sony and the HP both have two pysical buttons, but you can click on both at the same time and get the "third button" effect.
3. actually, at the "shop", where we have some 300 laptops, I haven't ever seen one of them without an external mouse; apparently, politicians can't use the trackpads to save their lives... :-D