It has been good to use as an introduction to a unit/topic... I just cut and paste the wikipedia article... and then with students, they make predictions about what our next unit will be about/events that will happen based upon the words given..
It also works as nice unit recap writing assignment.... having them write a paragraph, short essay, etc. about what our unit of study using the Wordle as a "word bank" for their writing...
Also, using it as a "word bank" we have used it for creative writing assignments... they used a Wordle on the Industrial Revolution to write fictional stories as kids living through this time period..
So, I guess all in all we use it as a "word bank".... I too would love to hear others teachers are using it. It def. has potential!