Zineb Ait Bahajji and Gary Illyes, Google Webmaster Trends Analysts, wrote the post together trying to break out the possibilities into three categories: (1) Having one home page that shows all users, no matter of language or location that same home page. (2) Bringing users to a landing page asking them to pick their desired home page. (3) Automatically redirecting users to the proper home page based off of various location/language detection techniques. Google supports all these options but gives guidance in this post on how to handle it in all these cases. Get the full story at Search Engine Land and Google