What determines relevancy?
The submission must ideally be a blog or article about XMPP/Jabber and/or XMPP-based software (clients, servers, libs).
Some exceptions might be made, for example for a release page showing a new release of some XMPP-based software.
However, marketing brochures (e.g. single-page marketing sites) for new products which don't contain information on XMPP, won't be included.
Extensions and specifications
Using XMPP to control robotic telescopes: http://www.astroscu.unam.mx/rmaa/RMxAC..51/PDF/RMxAC..51_articulo06.pdf