It has been officially launched only in Russia thus far, but it's clearly bound to become available elsewhere very soon. In fact, Samsung Hub has learned that the Galaxy S Plus will reach the Netherlands in the not so distant future. Unfortunately, there are no more details as of yet – we don't know anything about an actual release date or pricing. For figuring out the latter we can't really rely on the details in Russia, as that's usually one of the most expensive markets for unlocked devices (and the Galaxy S Plus is being sold there for around EUR 540).
source: Unwired View