Recent progress in the discipline of computer applications such as the advent of web-based communication, afforded by the Web 2.0, has paved the way for novel applications in language learning, namely, social networking. Social networking has challenged the area of Computer Mediated Communication (CMC) to expand its research palette in order to account for the way individuals engage in processes of learning and socialization, the way they interact, and the way they construct and perform their identities. With this in mind, it is necessary to examine the new material conditions, social arrangements, and the communicational landscape of Social Networking Sites (SNS). This study focuses on SNSs for language learning (SNSLL) and examines the particular case of Busuu. Drawing on theoretical tenets of sociocultural and ecological approaches combined with multimodal social semiotics, this research aims to analyze the views of language and learning that are enacted through the semiotic design of Busuu. It also purports to examine the types of identities wherein users are positioned through the compositional elements of this participatory online environment. The research design is informed by the principles of a qualitative case study and autoethnographic research. The data collected for this study consist of documentary information obtained from Busuu and the autoethnographic accounts of the researcher, who participated as a member of the Busuu community for 10 weeks. Results indicate that overall Busuu is an ecological system composed of sub-systems of nested views about language, learning, and users in which multiple timescales, spatiotemporal, and discursive resonances of various theories work in synergy. Thus, the semiotic spaces of Busuu combine structural, interactional and ecological views of language. Similarly, Busuu crystalizes views of learning that echo behaviorist, cognitivist, and constructivist theories. The website enacts different identities, positioning users as learners and teachers/tutors who are members of an imagined community. The study draws implications about the need for theoretical coherence and pedagogical alignment among the different components of the language curriculum (e.g. language and learning views, instructional activities) of Social Networking Sites for Language Learning.