If you haven't already, when you connect to Xbox Live today, you'll get the console update that finally does away with Microsoft points. I logged in just now and had 680 points turned into $8.50.
Microsoft has said this was coming for some time, but now it's official. There are still a few quirks with how Xbox Live will handle this converted money. For starters, any points balance turned into real moolah is valid until June 1, 2015. Second, anything you buy with that converted currency will not be subject to sales tax. However, Xbox Live will charge local sales tax on future transactions.
What about points cards? You may still buy and convert them to real cash. An FAQ (yes, I love saying "an FAQ" just to confuse those who read that word phonetically) on the conversion is here to answer all of your questions.
Now, to see if I can convert this Confederate currency into Microsoft points into U.S. dollars ....