US iTunes Store, Mac: Tried to use my usual Visa Debit card in the iTunes store this week to (finally) do the iTunes Plus upgrade to my purchased music. I kept getting messages that iTunes couldn't process it. Well, I would get one e-mail per day, despite how many times I updated the information. It locked up my card (of course), and it blocked another transaction. I got that cleared. I switched to another Visa card (but NOT a debit), and the iTunes Plus upgrade finally went through. Today, just to make sure it's all good, I called my bank. THe person on the line was telling me about some sort of "ban" on iTunes purchases over $40 on Visa. It wasn't clear if this was only Visa Debit, but since it went through on my Visa Credit Card, it must not be for all Visa. Couldn't find anything at Apple or Visa regarding any stated limits. I recall having a similar problem last year when renewing my MobileMe account. Again, the amount was over $40 after taxes... Anyone else have a similar issue?