Today the European producer Shijima made a post on the European SOCOM boards detailing some server changes and restrictions, which will be implemented in patch 1.60.
Well, I'm not sure how well this will be received as some people don't seem to understand exactly what goes into making a game and how complicated the process can be, but I sincerely appreciate the patience of those who do understand and who have done their best to 'enlighten' others.
I can now confirm that Slant Six Games and SCEA have agreed to implement some functionality into the game that will allow people to restrict the games they play only to the region they are playing in. The most straightforward solution to this challenge (and yes, it was a challenge to retro-fit something into the base techology) is to set-up different channels for different regions, as well as an overall global channel. Medley and custom games in the regional channels will be available to players who have chosen that region only. Medleys and custom games in global channels can be played by everyone, with all the associated risks and potential for abuse that entails (you have been warned!).
This is due for implementation into patch v1.60 because the team have been too busy working on implementing tournament and clan ladder functionality into v1.50. This is also the reason why it's taken a little time to establish a solution to the problem, simply because the team have been too busy working on resolving issues with the current patch in development and haven't had the bandwidth to focus on extra feature requests.
Perhaps people can bear that in mind in future...