The Date column on your Account Activity page shows pending transactions that have not yet posted to your Card (reflected with a date of "Pending"), as well as items that have been posted (reflected with the post date, e.g. 07/11/2011). To understand the difference between the two, it's helpful to review the posting process.
When you use a Chase Liquid Card to complete a merchant transaction, you have authorized the purchase amount. These transactions will not be posted to your Card until the bank receives and processes them.
For most merchant transactions, the merchant knows the exact amount of the transaction. For example, if you buy $82.75 worth of groceries, you have permitted the merchant to authorize the purchase amount with the Chase Liquid Card issuer. That amount would then appear as a pending transaction on your Account Summary until it was received, processed and posted by the bank.
Sometimes, though, the merchant doesn't know the transaction amount until after the purchase is complete. A good example of this is at the gas pump. Before you fill your gas tank, you're asked to swipe your Chase Liquid Card to approve your purchase. A $50 charge may be placed on your Card temporarily until it's replaced with the actual purchase amount. For example, if your gasoline purchase is $22.50, then that amount will be paid to the merchant and posted to your Card. However, you may see a $50 charge in the pending transaction section of your My Accounts page for 1 to 3 days until the merchant submits the actual amount of your purchase. You should always immediately deduct the actual purchase amount from your balance, even though it could take a few days for the money to be taken off of your Card.