The Web is constantly evolving into an unprecedented and continuously growing source of knowledge, information and services, potentially accessed at by anyone anytime, and anywhere. Yet, the current uptake rates of the Web have not really reached their full potential, mainly due to the design of modern Web-based interfaces, which fail to satisfy the individual interaction needs of target users with different characteristics. A common practice in contemporary Web development is to deliver a single user interface design that meets the requirements of an “average” user. However, this “average” user is in fact an imaginary user. Often, the profiles of a large portion of the population, and especially people with disability, elderly people, novice users and users on the move, differ radically. Although much work has been done in the direction of providing the means for the development of inclusive Web-based interfaces that are capable to adapt to multiple and significantly different user profiles, the current evolution towards the semantic web poses several new requirements and challenges for supporting user and context awareness. Building upon existing research in the field of semantics-based user modeling, this paper aims to offer potential new directions for supporting User Interface Adaptation on the Semantic Web. In this context, the benefits gained from supporting semantically enabled ontology based profiling are highlighted, focusing on the potential impact of such an approach to existing UI adaptation frameworks.