This paper reports on a case study of university lecturers' professional learning about digital technologies over four years, and their development of associated innovative teaching practices. During the first year, new hardware and software, as well as planned professional development (PD) opportunities, were made available to assist lecturers involved in initial teacher education in a Faculty of Education at an Australian university to integrate digital technologies into their teaching. Over the 2011-2014 period, some transformed their teaching practices substantially. It turned out that the provision of formal PD was only a trigger--much unplanned and unanticipated professional learning occurred through informal interaction, with lecturers co-learning with colleagues, and indeed with students, in an environment of enthusiastic experimentation. Formal learning was thus complemented by a networked model of the spread of knowledge and skills among colleagues, students, and wider educational communities. This paper, which focuses on the learning of two staff members who changed their practices considerably, suggests that educators benefit from a combination of formal and informal professional learning strategies when it comes to integrating digital technologies into their practices in pedagogically innovative ways.