>When I charge something against my bank card, debit or credit, my available account balance almost immediately reflects that amount. When I have money tranferred into my bank account, PayPal or a refund on a purchase, I usually will not see anything regarding that transaction from 4 to 10 days. Why is that? It makes me feel that the entire commerce system is evil and only out to screw with my money.

Absolutely right. It's the same thing when I go online and make my visa payment. The debit amount is reflected in my bank account display immediately, but the credit amount doesn't show up on my credit card display for at least another day.