I became aware just today of the magnificent green-blob astronomical object called Hanny's Voorweep at Cosmic Log: here, which I saw because CL is on my feed.
An even BETTER explanation complete with a magnificent evolution diagram can be found: here at Universe Today, a website I didn't even know existed until I Googled Hanny's Voorweep. Definitely going to add UT to my feed.
Update (1/11): Phil Plait at Bad Astronomy weighs in on the subject: here.
Update (1/12): Centauri Dreams gets in on the action as well: here.