At some point over the last couple of days, Microsoft made a small yet significant adjustment to how you buy Microsoft points online. Notice the difference?
That's right, now Microsoft points are sold in North America in increments of 400, to better match the normal pricing of Xbox Live Arcade titles and downloadable content. Previously, for an 800 point title, we'd have to purchase 1000 Microsoft points, as the batches were sold in increments of 500. Either that, or pick up a point card, which would mean leaving the couch, which I'm pretty sure is illegal.
Hopefully this means less leftover points in our Xbox Live accounts, and less OCD-fueled purchases of unnecessary themes and avatar clothing.
Thanks to bowen13 for pointing out the change!