Traditional User Experience (UX) research provides insights into situated uses of products, or reflections after their use, but tells us little about how products are experienced before use. In this article we demonstrate how people's engagement in web-based discussion forums creates ways through which they can experience products before they have actually used them, and reflect on the implications of this for UX research. To understand how product anticipation emerges in a digital-material setting we undertook an ethnographic analysis of members' contributions to http://www.teslaclubsweden.se, a web-based discussion forum that connects Tesla car enthusiasts. Anticipation developed as a shared endeavour that evolved through five ways which forum members engaged and participated in their community of practice. Through their online interactions their UX evolved before using the actual car. Our findings provide deeper understandings of anticipatory UX, and insights for UX design in HCI. © 2018 Association for Computing Machinery