Sprint held their 9th annual developers conference this week and lots of Android bits are still slipping out. I previously reported that this was coming, but Sprint confirmed that they aim to add carrier billing for application purchases on all storefronts, including the Android Market. Hopefully, this will increase app purchases since customers will not be forced into signing up for a Google Checkout account. No word when this feature will become available, but more payment options is always better for the consumer.
I anticipate we will see a similar carrier billing option from T-Mobile as well.