  Many Web-based data sources and services are available as feeds, a model that
provides consumers with a loosely coupled way of interacting with providers.
The current feed model is limited in its capabilities, however. Though it is
simple to implement and scales well, it cannot be transferred to a wider range
of application scenarios. This paper conceptualizes feeds as a way to serialize
query results, describes the current hardcoded query semantics of such a
perspective, and surveys the ways in which extensions of this hardcoded model
have been proposed or implemented. Our generalized view of feeds as query
result serializations has implications for the applicability of feeds as a
generic Web service for any collection that is providing access to individual
information items. As one interesting and compelling class of applications, we
describe a simple way in which a query-based approach to feeds can be used to
support location-based services.
