What is the difference between the Standard and Business options in PayPal?

The differences between the two Payment Options are as follows:

PayPal Standard PayPal Business
Should I have a US based PayPal account? No Yes
How much will I be charged as transaction fees? % of the amount Flat fee of 50 cents
Should my customer have a PayPal account too? No Yes
Can my customer pay via credit card? Yes No
Will I receive the payment instantly? Yes May be delayed for eCheck payments