Microsoft confirmed that the plan going forward is to phase out Microsoft Points and move to a real currency model.



From Fudzilla:

While Microsoft will start this transition this fall, those that have Microsoft Points should not feel rushed to spend them or use them, as Microsoft will credit existing points to your account with the equivalent real currency amount that is equal to or greater than the amount of Microsoft Points that you have.

In the short term, once the transition takes place users will still be able to redeem Microsoft Points cards; but these cards will be converted into real currency, which would then be deposited into your account. Microsoft Points are going away, but the good news is that Microsoft seems to have a good transition plan in place to take care of this.

  Microsoft Points will be converted to real currency