According to wikipedia, a landing page is built to convert leads from an email, social media, ppc or search campaign. They are an important tool in any online marketing campaign and are effective in converting browsers into clients. The landing page contains detailed information about the specific product or service that is mentioned, especially benefits and features. It should be considered part of the marketing campaign and shouldn’t just be another page on your website.

Courtesy of MarketingSherpa
Using landing pages can significantly impact your conversion rate. A survey by MarketingSherpa asked marketers the effectiveness of dedicated landing pages. 43% of marketers found it extremely effective with 49% finding it somewhat effective.
Another survey by Atlas Onepoint, found that the average conversion rate when companies used their homepage as the destination for an advertisement or link was only 6 percent. However, companies that used targeted landing pages had almost double the conversion rate, with 12 percent of their visitors converting.
Another survey by Atlas Onepoint, found that the average conversion rate when companies used their homepage as the destination for an advertisement or link was only 6 percent. However, companies that used targeted landing pages had almost double the conversion rate, with 12 percent of their visitors converting.

Couresy of MarketingSherpa
The following chart on the right indicates the effectiveness of a landing page by website objective. Almost across the board, it has been found that landing pages are valuable for all types of actions, including ecommerce purchases.
So, if you want a solid argument to create a dedicated landing page to convert your browsers, look no further than these stats.
At the least, you should optimize your core service pages on your website to target and convert browsers - either for lead generation or transactional opportunities.