Doesn't this need to be country-specific, potentially both for the country you are living in and the country you came from?
Should these country-specific questions also go here, or to, for example, the China forum?
There are many questions which are fairly general and not country specific. I will post some example later on.
Also, I disagree that making this country specific is useful or feasible. I am sure that it is not appropriate to advocate 100s of different sites on expatriation, as there are hundreds of countries.
Most expats face the same problems no matter which country they live in.
Although many of the questions on the site are country-specific, there is nowhere near enough activity for any individual country to justify a dedicated site (in fact, the site as a whole is still struggling to get out of beta).
Ultimately, country-specific questions get country-specific tags, and users can subscribe/ignore at their leisure.
Although I can't claim to make a prediction with any degree of accuracy regarding what the Expats site would look like, I think we would see similar trends emerge.
Some people are accidental expats, getting posted to a country that their employer decides on. So yes, they are only really looking for information on that one country.
There's perhaps a larger group that are actively choosing a country, either from a range of options provided by an employer (or contract agency), or to move to start a new life, or maybe to retire to. For this group, it's very useful to have an area to ask questions that isn't going to be weighted to just one country.
A significant number of issues that expats face are common as well regardless of the destination country. For example Americans have tax issues that are different from most other nationalities (based on citizenship not residence). British expats might have questions about how to retain a bank account back home. All regardless of the country they find themselves an expat in.
The Stack Exchange tags will allow questions to be filtered. These should be set up to allow tags for both the country you are an expat from (often the same as nationality), and separately the country you are an expat in. Then somebody can search for all questions affecting Swedish expats, and/or all questions about living in Turkey.
As a serial expat myself, I've got to say that I don't think this will work unless it is country-specific. Expats' bread-and-butter concerns (visas, jobs, housing, schools, banking etc) vary widely from country to country, and genuinely useful advice ("to get the fingerprints for the Singapore criminal record application needed for the Australia 856 visa, go to this notary in Melbourne") is by necessity very, very specific.
Then again, I would also have thought that a generic programming Q&A site would never work, but all languages seem to coexist pretty happily on Stack Overflow...
It is impractical to divide up by country. There would need to be a site for every combination as there will likely be very different answers for "How do I register a European car in the UK", "How do I register a European car in Grenada" and "How do I register a South Korean car in the UK".
Since there are 249 places with ISO-3166 codes that would make 249 x 249 = 62,001 different sites. Including grenada-to-japan.stackexchange.com with an expat population of one. There are a dozen countries/regions on that list of which Japan has under ten immigrants from.
If we just stick them all on the same site with to-uk and from-eu, our South Korean immigrant to the UK would benefit from knowing the general process in the UK, even if the South Korean portion of the process may be different. Or the EU resident would get a better idea of how to export a car from the UK answer even if they are actually moving to Grenada.
Allowing the questions to co-exist as jpatokal so eloquently said would allow US expats to every country to read up on the Foreign Earned Income Exclusion while teaching expats from all countries how to register a car purchased in the UK, or what documentation is needed to open a bank account in Namibia.
This would create a richer knowledge base for future generations (not to mention consolidating eyes).