I'm waiting on something from Tampa, FL. The seller called me Thursday morning after he had sent the package and gave me the tracking number. The first time USPS acknowledged that the package existed was today, 2 days later as it was mailed. This was as the package was leaving the Tampa processing facility on the 9th which was yesterday.

I get packages all the time where the tracking still says there is no record for that tracking number. This system is too dependent on various mail personnel at various points to actually scan the package into the system.