We met for about an hour to discuss some dream features we'd like to see in Mapnik in the year(s) to come, who's using Mapnik currently and for what, and some specific third-party tools that exist or should exist in the future for working with Mapnik.
Dane Springmeyer took notes. Please add to them if he missed anything!
Currently running on SVG symbol support patch written by Koordinates (Robert Coup/Craig Destigter)
Actively needing C++ based WMS server
Stamen has ideas around compositing/blend modes in mapnik.Image
UrbanMapping may have some code that does some of this already (outside Mapnik) and can possibly share
More control needed to restrict certain application of symbolizer to features with given geometry type
GeoCommons usage has run into issue. Easy to work around, but would be nice to make easier to control
Must add ability to try various placement directives, e.g. in cardinal directions (Jeff Johnson)
Aubrey Holland has some github code that lightly wraps, but he mostly uses Python+TileCache still at this point
Support for Cascadenik (CSS) natively in Mapnik
Mapnik currently uses boost property_tree to handle XML (along with Parser)
Expressions are needed for dynamic, data driving symbolizers
Jeff Johnson (opensgi.com)can offer data scenarios for profiling massive tile deployment situations
Supporting non-relational datastores
Fuller MemoryDatasource support for Lines and Polygons (currently Mapnik only supports in memory points)
Implement pluggable python-based datasources (using boost::python)
Python reference server available as a comparison - https://github.com/mapnik/OGCServer
A self contained Map package - term coined by Andrew/Jeff
Could allow shippable GeoCommons map, e.g. download and open/browse in QGIS offline.
Prototype will target Mapnik XML/Cascadenik MML + sqlite datasources + zip archive
Need to start thinking through tools that can read, unpack, and pass this bundled format to render with Mapnik
Has features that push forward ideas around SFM