• by Mark Walsh  @markfwal, January 21, 2014

When Twitter began allowing images to display directly in a user’s timeline last fall, complaints quickly arose about clutter and the growing commercialization of the microblogging service. But don’t be surprised to see more pictures popping up on Twitter.

Tweets that include links to photos, along with image preview images that appear in a user's Twitter feed, draw 150% more engagement than the average for brands, according to a new study by social media analytics firm Simply Measured.

The report analyzed Twitter activity among the Interbrand 100 companies, as well as the Forbes 100 Best Small Companies in America during the fourth quarter. For the Interbrand 100, tweets with links to Pic.twitter.com -- Twitter’s own image service -- had an average of 210 engagements (mainly retweets or “favorites”).

Tweets with links to material on Tumblr, Pinterest and Vine were the next highest-performing types, with 125, 94, and 72 engagements per post. Overall, tweets with links generated more interaction than those without. Tweets with no link, for example, saw 79% of a brand’s average engagement, while those with two or more had 150% of the average.

The top 10 brands (by engagement) of the Interbrand 100 list accounted for 60% of all brand engagement in the fourth quarter, with eBay at No. 1, followed by MTV, Amazon, Starbucks and McDonald's. Retail brands led by eBay and Amazon saw the most interaction in the holiday period, followed by those in the restaurant, media, technology and auto categories.

The research showed a wide gap between the Interbrand 100 and Forbes 100 in Twitter activity and engagement. Brands in the former group posted an average of 12 tweets per day, compared to only three among the top small businesses. The biggest share of large brands (42%) tweeted one to five times a day, while the majority (56%) of small ones didn’t post daily.

Companies in the Interbrand 100 had an average of 870,000 followers, while only 17% of the Forbes 100 averaged 5,000 or more. Among other key findings:

*Over 36% of all brands contain links

*Brand audiences on Twitter this quarter grew by 20%

*98% of all brands are active on Twitter

 *58% of top brands have a Twitter audience of 100,000 or more.

The results are based on Simply Measured’s tracking and analysis of 129.3 million brand tweets, 12.7 million engagements (@replies, mentions, retweets and favorites), 476,000 links and 527,000 hashtags. Tweets and engagement averages excluded brands inactive during the study period, from Oct. 1 to Dec. 31.