2009 was a tough year for everyone but things are looking up. Comscore today released its 2009 U.S. Digital Year in Review, a recap of key trends in the U.S. digital media landscape (including e-commerce, search, online video, online advertising and mobile) providing some insights into how digital marketers can capitalize on these trends in 2010.

Key findings from the report include:

- The U.S. core search market grew 16 percent in 2009, driven by a 6-percent gain in unique searchers and a 10-percent gain in search queries per searcher. Google and Bing led among the core search engines in terms of increases in market share.

- Social networking continued to gain momentum in 2009 with nearly 4 out of 5 Internet users visiting a social networking site on a monthly basis and Facebook and Twitter propelling much of the growth in the category.

- Display ad impressions grew 21 percent in 2009 as the online advertising sector increased its share of media spending. Growth was driven by an 8-percent increase in ad reach and a 12-percent increase in average frequency.

- Total (retail and travel) U.S. e-commerce spending reached $209.6 billion in 2009, down 2 percent versus the previous year and the first year on record with negative growth rates. Nonetheless, e-commerce retail spending continued to increase its share of consumer spending in a challenging economic environment.

- Six out of seven U.S. Internet users now view online video content in a month, with YouTube and Hulu continuing to experience rapid increase in viewership.

- In the past year, the mobile industry witnessed smartphone ownership increase from 11 percent to 17 percent of mobile users, while 3G phone ownership increased from 32 percent to 43 percent.