I demonstrate a sociocultural approach to Twitter as a literacy practice, making use of a media ecology framework. I demonstrate how Jonathan Agnew, the BBC's cricket correspondent, appropriated Twitter as part of his engagement with Web 2.0 literacies. I situate this within an approach to understanding BBC Test Cricket journalism, taking into account historical, cultural and economic factors. Through deploying flexible ethnographic methods in a longitudinal study I explore three issues. I present evidence as to his attitudes, including in relation to other communications technologies he uses. I study his use of linguistic and other semiotic resources on Twitter and demonstrate the different kinds of roles played by others. His attitudes are mostly extremely positive, but vary in degrees of integration with other communications practices and fluctuate in response to abuse. His use of Twitter including with images is skilful and highly dialogic. Particularly interesting are short stories co-constructed with others, through which elements of apparently backstage identity are performed. I show how practices of this ʺchange agentʺ can be approached in the context of his overall professional practice and that of cricket, as a specialist media domain in a particular era.