So my router pulls IPs of the people i connect to and after i got done playing tonight i decided to look up some of these IPs just to see if playing with my eastern time zone friend was matching us up with mainly east coast players. Well after looking up a handful of ips not only did i notice most of them were east coast (i live in colorado and was hosting the lobby) but there were some ips from places i didn't expect. Places like russia, china, and even southern Australia. How/why do they throw people from SO far away into the same lobby? It seems like this SHOULD be impossible because it would create laggy lobbies and would just overall be a very unenjoyable experience for atleast one party involved.
It can depend on so many factors. For example, you could have a better connection with someone in a different city to someone who's next door if you're on different ISP's and have routes with lower latency to the person further away. In saying that, the locations you mention seem extreme.
Although I'm in the UK and get placed in lobbies with people located in France a lot. However, I get laggy games all the time, yet I can be in lobbies with Italians (which is further away) and never have any issues. So I can only assume the ISP I'm with has better connections to Italy, but latency laden connections to France. However, it's not to the extremes as you're seeing where I'm matchmade with people in Australia or South America or something.
Who knows though as there's so many variables that can affect your latency, some of which can be in your control and some out of your control.
its because they removed the region lock, they've only being making cod for a decade, their still not very good at it bless them.
I recently changed my connection to OPEN NAT (forwarded ports etc) and my games became almost unplayable. I was being dropped instantly yet it was taking me an age to kill other players. It seemed that I was pretty much host 9/10 games (I could tell as I was first to load in game).
I decided to reset my router and it is now Moderate. I no longer get host and my game experience is a million times better.
Try it, you never know!