Should Digital News Articles Reference Their Dead Tree Counterparts?

If you read the New York Times closely, a new change has appeared in the digital edition.

At the bottom of every article, there is now the following note in small, bolded font:

How interesting, no? For the first time, a newspaper's website references exactly when and if the article ran in print.

It's an interesting problem to address -- from the eyes of a digitally-minded person, it shouldn't matter, but from the eyes of a print-minded person, it's necessary ("...didn't I read this before?"). Instead of noting at the top -- "online only," for example -- the Times just placed notice at the bottom.

I'm all for an increase in information -- makes everything easier to categorize and what have you -- but it makes me wonder just how much it's worth it. Will they backdate old articles with such information?

And what's next? PDFs of the article as it printed? (Could be a lucrative source of additional ad revenue, since the ads can be reproduced in the PDF and also monetized by how many downloads occur.)

Hmm.