Industry tracker eMarketer forecasts that YouTube will rake in about $5.6 billion from ads this year, pocketing nearly two billion of those dollars as profit.

The Google-owned online video sharing venue should net $1.96 billion, after divvying YouTube ad revenue with partners and creators of content, in a 65.5 percent jump from what it netted in 2012, according to eMarketer.

YouTube's expected 1.7 percent share of digital ad revenue worldwide will top those of Twitter, Amazon.com, LinkedIn, Pandora, AOL, and Millennial Media, the market-tracker said in a released forecast.

The $1.08 billion in ad revenue YouTube will reap in the US alone will equal 6.3 percent of Google's total ad revenue here for the year in a 51.7 percent increase from 2012, according to eMarketer.

"Video ad revenues are expected to increase significantly in coming years for YouTube's US operations, particularly as mobile video viewership grows," the market analysis firm said.

EMarketer credited the growth in YouTube advertising to increasing appetite for online video on mobile devices and efforts by Google to provide advertisers ways to reach people on the array of screens in their lives.