Taco Bell bumped McDonald’s out of the No. 1 spot in the first-quarter Restaurant Social Media Index from DigitalCoCo.

This marks the first time Taco Bell has led the Top 10 ranking. McDonald’s came in at No. 2; Wendy’s, No. 3; Starbucks, No. 4; and Buffalo Wild Wings, No. 5.

McDonald’s held the top spot in the fourth quarter of 2012 after Starbucks had held the position for six quarters, said DigitalCoCo founder and chief executive Paul Barron.

“Taco Bell has had some aggressive growth across the three platforms that we measure, which are sentiment, engagement and influence,” Barron told Nation’s Restaurant News.

“We get the feeling that the brands at the top are jockeying with programs that ramp up engagement, or maybe they are doing something on an offer that are causing guests to interact more, or their sentiment is greater because of a new menu item that gets a lot of social fluff,” he said.

Longtime RSMI star Starbucks’ decline in the rankings was more about sentiment than anything, Barron said. “It’s hard to tell if it’s because Starbucks hasn’t done anything cool or new to pump up sentiment around the brand, or are we getting a little bit of fatigue in the brand? We don’t know,” he said.

Apps, payment options drive mobile results

The RSMI also tracks and ranks brands based on mobile engagement. The index currently only takes into account social transactions via mobile devices, Barron said, noting that Red Mango, Einstein Bros. and Panera Bread have found success in that area.

“All these [brands in this category] have really embraced app development in mobile,” he said. “Because of that, we believe the consumer audience that they are reaching out to has a tendency to engage with those brands a little more frequently [than with others], and also in ways that are a little more ‘sticky.’”

For instance, Dunkin’ Donuts has sponsored contests; Buffalo Wild Wings added some gaming aspects; and Panera offered marketing programs around product awareness and sourcing, Barron said.

Mobile payment has also presented opportunities for brands. “Sweetgreen has done some interesting things with mobile payment, and we believe that’s caused these guys to get a lot more mobile engagement,” Barron said.

Sweetgreen’s mobile payment option, which is connected to a credit card account, is a combination of a loyalty program and a payment program, “much like you see with Starbucks,” Barron said.