Do you have to give up your credit card info and name/address to sign up for the Google app store? (In light of the recent story that app developers get all your info, I don't know if I want every 2-bit app to get that info. The info itself could be worth more than the 99 cents for the application.)
No, you can use a regular google account. However, to pay for an app you will need to do so
Not exactly. I don't know if this is a Sprint thing or not, but if I'm on data and not wifi i can have my apps billed to my sprint account. However I don't know if this applies to in app purchases as I don't use them.