Barack Obama, Justin Bieber and the Newtown tragedy are among the topics covered in this week's edition of top Twitter pics.
Photo-organizer Skylines sorted through 32,980,627 unique images from the past week, and compiled the most-shared and retweeted on the microblogging site. Click through the gallery, above, to see the top 10.
Any good ones we missed? Let us know your favorite photos from the week, in the comments below.