Abstract
This paper examines some of the possible consequences of the introduction of online Geographical Information Systems (GIS) for the social politics of neighbourhoods and the public sphere more generally. Summarizing a number of recent theorizations of neighbourhood informatization, the article provides examples of online GIS in the UK and considers some of the possible implications of the use of such technologies for contemporary debates about citizenship in the context of processes of ‘splintering urbanism’. Arguing that social citizenship is best understood in terms of varying forms of ‘proactive’ or ‘defensive’ engagement, the paper explores the relationship between virtual decision making about neighbourhood choice and the impact of aggregated virtual decisions ‘on the ground’, before going on to consider how differentiated forms of engagement are producing new forms of social exclusion in changing urban spaces.