The ECB embarked on its "follow us" campaign at the start of the contest in Australia at the end of November.
According to the ECB, the number of unique users on its website was 572,000 in December, the highest month of the year, and well above the 300,000 average during the summer months.
One of the successes of its campaign was the video diary kept by spin bowler Graeme Swann, which recorded in the region of 750,000 views on YouTube.
The ECB's Twitter account almost doubled its number of followers from 17,000 to 31,000 over the series, which concluded overnight with a 3-1 victory for England.
A spokesman for the ECB said it had no plans to commercialise its online output and was focused on driving the popularity of the game.
The ECB is on the hunt for a new domestic Test cricket sponsor, after failing to agree an extension with utility brand npower.