I was reading a report this morning on the most recent business results for United States Postal Service and it made me think about how this is the real bellwether for multi-channel.  USPS lost over $5B dollars over the last year as customers change their preferences from physical mail to electronic mail - and their purchasing habits towards the internet.  The overall results for USPS were dire but there is a silver lining:

Letter volume declined - Total 2011 mail volume declined by 3 billion pieces, or 1.7 percent, from 2010.

But package volume increased - USPS Shipping Services revenue, which includes Priority Mail and Express Mail, increased $530 million in 2011 (6.3 percent)

A USPS official stated "The continuing and inevitable electronic migration of First-Class Mail, which provides approximately 49 percent of our revenue, underscores the need to streamline our infrastructure and make changes to our business model."  He continued " The increase in Shipping Services revenue was driven by strong growth in the Parcel Select and Parcel Return Services, due to increased mailings of packages, as customers continued to use the Internet more often to purchase products."

I think that we are still before the tipping point of electronic delivery vs. physical mail delivery.  With annual declines of only 1.7%, there is still substantial preference towards physical mail - but most anticipate this conversion to accelerate.