Email marketing or directly marketing a commercial message to a group of people using email is still a dominant form of marketing in the social media world. Researchers estimate that United States firms alone spent US $1.51 billion on email marketing in 2011 and will grow to $2.468 billion by 2016. The vast business opportunity has excited startups globally to tap it. Some have gone the way to build marketing intelligence for effective delivery of emails and others have decided to move ahead in the newsletter curation business, where by customers receive curated newsletters based on their industry interests either daily or weekly.