Email is always supposed to be in its death throes but it's far from keeling over. It's one of the last, if not the last, open communications protocol. It's still the dominant way to exchange files, have short conversations and subscribe to newsletters. Finally, marketers dropping email for purely social campaigns do so at a cost: The ROI of email marketing is $40 for every $1 spent. This infographic from startup Attachments.me supports the premise that email isn't about to kick the bucket.