@TommyDordo Ooh! Tough question! I imagine unless you have 'one foot in the U.S.' and 'the other in Canada', there's no way to tell. 
@Rae_Rae wrote:@TommyDordo Ooh! Tough question! I imagine unless you have 'one foot in the U.S.' and 'the other in Canada', there's no way to tell.
There is,
you're using Bing on the Internet, not physically stepping your foot in it.
on the Internet, your location in identified by your IP address. VPNs can change your IP address and allow you to access content from other locations.
@HotCakeX While I did not know that "VPNs can change your IP address and allow you to access content from other locations," I was seriously joking about having 'one foot in the U.S.' and 'the other in Canada.' You do get that (the joke), though, correct? (It is) because (both) the U.S. and Canada border each other? One foot here and the other there? ...hmmm. Maybe I am not as funny as I like to be- sometimes.
Meanwhile, 'the question' (Diff. between Bing U.S. and Bing Canada), I still believe is a tough one (for me to answer), because I may not understand why- or how useful it would be to- someone would want to change the/ their location on 'the regular.' What- if any- would be the point of doing so? (Please.)
In other words, How does a person use both at the same time? Why would a person use both at the same time?
@TommyDordo Please, forgive my ignorance. The question (you posed), "between Bing United States and Bing Canada which one has the most features? Which of the two is updated more frequently and new features added ahead of time?" is hard for me to answer because I do not use Bing Canada. It is also hard for me to understand why- or how, for that matter- a person could/ would switch between the two as needed to make such observations.