All of this depends on your card company (even debit) and the merchant bank used to process your payments. Usually any order or pre Oder is authorized at the first step. Even if it says $1, it has gotten authorization from the bank to submit the full charge. Most companies put the full charge amount as a "pending charge". I think they have 30 days to submit the final charge. Pending charges can disappear from your online statement in as little as 3 days. Sometimes they stay pending as long as 30. When a company decides that it is time (usually when you receive the merchandise) the pending charge goes a full charge and is put as a real debit in your card.
So if people are seeing charges disappear, they are just seeing the authorization disappear. The charge is still there, and will return when whoever you made the purchase from wants their money. In eCommerce, it is proper form to run the full charge when the customer gets their goods. Some companies jump the gun and charge you early. It's still legit.
I don't expect anyone will see their full charge appear on their statement until Friday. Maybe Thursday.