On the site itself, you need some words for those "Supported services" icons. I know the first is Facebook; the second I think is Flickr; the third is Picasa; I have no clue what #4 is.
In support of original post, I did not know what it was either. A simple tooltip or hover could have solved. Even if it was a title tag filled out for the image. Just saying that not everyone recognizes that icon
"It’s a fast, beautiful and fun way to share your life with friends through a series of pictures." - http://instagr.am/ Think twitter but with pictures.
