Undiscoverable dictionary feature in NYTimes.com

I just discovered a feature on NYTimes.com which I didn't even realize was available. 
1. Go to an article page, like this one
2. Find a word you don't know (or any word in the body of the article).  My word was Pablum
3. Double click on the word
Woah!  Definition popup!  That's actually what I was looking for! 
I was actually trying to right-click, but my finger twitched.  I knew that IE doesn't have a lookup feature by default, but I remember that there was a Firefox extension which would open dictionary.com in a new tab if you right clicked on a word.  I was secretly hoping that I had found and installed such a feature in IE 
Oh, well.  Pleasant surprise.  By the way, Pablum is  "A trademark used for a bland soft cereal for infants." 
And this week, no matter what happens, you're still in better shape than Antonio Gonzales.