Doing all your Christmas shopping for your distant desert-island-stranded relatives who you've not heard from in over a decade on Steam? Well, relish the convenience while you can, because Valve's added an option for developers and publishers to disallow cross-region gifting and trading. In addition to the obvious ramifications, this may pull the rug out from people who use those features to get around arbitrarily raised regional pricing and/or censorship. In the words of a handless person who's just come across the world's most pettable kitty, "bummer."
The new option was first discovered in the database of Metal Gear Rising: Revengeance (via NeoGAF). The new tag, "AllowCrossRegionTradingAndGifting," is set to "No" for Konami's cyborg ninja absolutely-positively-not-stealth game.
Before you panic, note that it only applies to Eastern Europe and South America at the moment. Prices are sometimes lower in those regions, so it may not be time to sound the alarms just yet. That said, the functionality could easily expand over time. Also of note: it apparently doesn't apply to retail keys.
I've mailed Valve with questions about the new limitations, and I'll pen some form of update as soon as I hear back.