Paid search advertising has not been without controversy and the issue of how search engines present advertising on their search result pages has been the target of a series of studies and reports by Consumer Reports WebWatch. The Federal Trade Commission (FTC) also issued a letter in 2002 about the importance of disclosure of paid advertising on search engines, in response to a complaint from Commercial Alert, a consumer advocacy group with ties to Ralph Nader.
Blogging website Tumblr first launched ad products on May 29, 2012. Rather than relying on simple banner ads, Tumblr requires advertisers to create a Tumblr blog so the content of those blogs can be featured on the site. In one year, four native ad formats were created on web and mobile, and had more than 100 brands advertising on Tumblr with 500 cumulative sponsored posts.
Twitter allows companies to promote their products in short messages known as tweets limited to 140 characters which appear on followers' Home timelines. Tweets can contain text, Hashtag, photo, video, Animated GIF, Emoji, or links to the product's website and other social media profiles, etc. Twitter is also used by companies to provide customer service. Some companies make support available 24/7 and answer promptly, thus improving brand loyalty and appreciation.
Websites such as Delicious, Digg, Slashdot, Diigo, Stumbleupon, and Reddit are popular social bookmarking sites used in social media promotion. Each of these sites is dedicated to the collection, curation, and organization of links to other websites that users deem to be of good quality. This process is "crowdsourced", allowing amateur social media network members to sort and prioritize links by relevance and general category. Due to the large user bases of these websites, any link from one of them to another, the smaller website may in a flash crowd, a sudden surge of interest in the target website. In addition to user-generated promotion, these sites also offer advertisements within individual user communities and categories. Because ads can be placed in designated communities with a very specific target audience and demographic, they have far greater potential for traffic generation than ads selected simply through cookie and browser history. Additionally, some of these websites have also implemented measures to make ads more relevant to users by allowing users to vote on which ones will be shown on pages they frequent. The ability to redirect large volumes of web traffic and target specific, relevant audiences makes social bookmarking sites a valuable asset for social media marketers.