Like the American Airlines spam, this one didn't bother to include any graphics to make it look official.  Further, it shows plainly that the link goes to www.usps.com.ww062.com (note that the domain is ww062.com).  Some scammers are just lazy.

Sender: auto-notify@usps.com

Subject: Delivery Confirmation

Text:
Dear Customer,

We attempted to deliver your item at 11:02 am on November 5, 2011 and a notice was left. You may arrange redelivery by clicking the link below or pick up the item at the Post Office indicated on the notice. If this item is unclaimed after 15 days then it will be returned to the sender. The sender has requested that you receive a Track & Confirm update, as shown below.

Label Number: 7007 3912 0928 2345 2874
Weight: 1.1 LBS
Expected Delivery Date: November 5, 2011
Service Type: First-Class Certified Mail
Service(s): Delivery Confirmation
Status: Final Notice

To check on the delivery status of your mailing or arrange redelivery please visit our website: http://www.usps.com.ww062.com/shipping/trackandconfirm.php?navigation=1&respLang=Eng&resp=11072011

Please make sure to print out your invoice in order to collect your package at our Post Office: http://www.usps.com.ww062.com/shipping/invoice.php?navigation=1&respLang=Eng&resp=invoice_11072011

Future activity will continue to be emailed for up to 2 weeks from the date of request shown above.

For more information, or if you have additional questions on Track & Confirm services and features. We're here to help. Call 1-800-ASK-USPS!