[Plugin: AddToAny: Share/Bookmark/Email Button]

Thanks for noticing. 🙂 It’s actually an IE-specific fix for this reported issue: http://wordpress.org/support/topic/plugin-addtoany-sharebookmarkemail-button-white-space-around-twitter-icon

It’s certainly more code output than I’d like, but it was the simplest most cross-compatible way to deal with the issue of opacity in IE iframes while still adhering to W3C validation standards.