I mailed a package on Feb 7 at the post office, and they didn't scan it into the system until Feb 10. It sat in their office for 3 days, and is one of the demerits counting against me at Ebay as well.

Meanwhile, the customer got mad because they thought the Feb 13 predicted delivery date from Ebay was a guaranteed delivery date, and when they noticed it wasn't scanned until the 10th they thought I was jerking them around (I had assured them I mailed it on Feb 7, but there is no proof of that). I got a nasty message from the buyer - but I never got positive feedback or an apology when the item actually arrived on Feb 12.