Difficulties getting Technical Info

Yesterday a sales person (albeit for phones) at a Futureshop assured me
that Ipod Touches could not have their operating systems upgraded. "Only
Iphones". Even though a customer said she thought she had upgraded her
touch.

Googled sites seem to disagree,

On a parallel note, I have been told by someone my age that he is typing
on his Ipod with a usb connected keyboard. The net disagrees.

Futureshop has a bluetooth dock for a usb keyboard.
Not clear how all this fits together.