2011 Go Green Stamps To Be "Re-Released" In 2012?

Never heard the USPS use the term "re-release" in reference to commemorative stamps before, but according to some news articles today the USPS is re-releasing the 2011 "Go Green" stamps in anticipation of Earth Day 2012:

http://www.miamiherald.com/2012/03/...n-pride.html

Is this just a news promotion? Is there any philatelic interest in re-releasing these stamps (i.e. is there to be a different plate number used?) or is just a marketing ploy to generate interest in using up old inventory?

What I find interesting is that this apparently hits the newspapers (presumably by a news release) yet nothing is mentioned (at least not yet) on the USPS's website about this "re-release" promotion.

I've never heard of a "re-release" for commemorative stamps either. Sounds like tying this to Earth Day is an attempt to fool the public in order to reduce old inventory.