I was just wondering how it is decided which tags are rendered into the official OSM maps? E.g why are there car parking spots shown in the Maplink map but bike parking are not (not even in the Cylce Map). I can understand that not everything is rendered to avoid a visual overload but would like to understand the way tags are selected. Many thanks in advance!
The mapnik layer does not render everything, it is designed to be a mapping style which is cartographically coherent. One of its maintainers is Steve Chilton, President of the British Cartographic society. It is possible to add tickets for additional rendering at trac.openstreetmap.org, but ultimately the decision lies with the maintainers of the Mapnik stylesheet. Steve gave a talk about the things he would like to add at State of the Map 2010, the slides may be on the web somewhere. For a change to be successful, I’d recommend identifying what needs to be added to the Mapnik stylesheet, and attaching a diff on the trac ticket, as well as providing several examples, and preferably an example of the envisaged output.
CycleMap is designed, operated and maintained by Andy Allan: styling and rendering are his choices: it’s his project.