It goes on your account as a pending transaction. Look at the online banking info at the top, there will be two areas, a pending and then another area below for cleared transactions.
Pending to a vender means it is a hold, but in reality the buyer can not use the money and it is in limbo, so really you are charged in a way. I mean you have no access to that money. The bank has not processed it so they have not technically taken the money out of your account either and can not let you use the money, again its in limbo. As Shane says it can drop off. I have seen clients of mine have a pending transaction for 6 weeks, so it may or may not drop off. And I have a feeling that in this case it is not going to drop off unless the vendor can not fulfill your order.
Technically the payment should not clear until the vender ships the item. Some will even say it is a law. In most states it is not a law, but an agreement with the credit card company or just a business guide a state issues to follow. Every state is probably different on this.
Because I use separate money for tools this is one reason I just could not see forking out 2000.00 for tools that I know for 2 weeks I could not use and then might not even get the tools! Yeah I would get the money back, but this way I can use that money in the meanwhile. So I will wait until Feb 1st and take my chances.
I remember staying at a hotel once where the entire 2 week stay was prepaid months in advance. When I got there they wanted a credit card. They put a 2500.00 hold on the card without even telling me and that was what I was going to use for spending money! Man I was pissed when I went out for dinner that first night and the card was denied and I found out what they did ! Even with the room prepaid they still put up a pending transaction! Back then we used travelers checks so we had money, still I have hated the pending system since. I guess it is needed though, just be careful with some venders and how they use it, especially hotels.