How long does it take for Apple to bill me for purchases on iTunes? I've noticed that I'll often get an email about 24 hours after my purchase took place on iTunes. Does Apple have some sort of billing cycle, or does the withdrawal frm my account actually happen immediately?
Per the iTunes Store — Terms and Conditions


  If a credit card or your PayPal account is being used for a transaction, Apple may obtain preapproval for an amount up to the amount of the order. Billing occurs at the time of or shortly after your transaction. If you are using 1-Click purchasing or your PayPal account, your order may be authorized and billed in increments during one purchasing session, so it may appear as multiple orders on your statement. If an iTunes Card, iTunes Store Gift Certificate, or Allowance Account is used for a transaction, the amount is deducted at the time of your transaction. When making purchases, content credits are used first, followed by Gift Certificate, iTunes Card, or Allowance Account credits; your credit card or PayPal account is then charged for any remaining balance.