SAN FRANCISCO (CBS SF) – Twitter (TWTR) is buzzing Monday with reports that co-founder Jack Dorsey is going to step down as CEO at mobile payment startup Square, and take over the permanent CEO gig at Twitter, where he’s serving on an interim basis following the resignation of Dick Costolo, who’ll reportedly step down from Twitter’s board when a new CEO is named.

At the same time, Dorsey disclosed that he bought more than 31,000 Twitter shares on Friday, adding to his big stake in the firm. A number of other executives also bought big chunks of the stock, which had fallen to a post-IPO low following another disappointing earnings report.

Twitter is also getting credit for a deal announced with the NFL today in which the league will give more access to NFL content to Twitter users, with Twitter looking to benefit from heavier advertiser interest.