Projects that I hope to see people joining from: TileCache, Tirex,
Mapproxy, GWC, others, etc.
This list will be discussing general tiling ideas -- how to cache tiles,
how to manage caches, how to work with limited caches, where to put your
tiles, things like S3, etc. etc. If you are at all interested in tiling
-- not at the level of a specific application, but in general -- please
join the list.
Additionally, if you are interested in discussing providing feedback to
the OGC regarding the WMTS spec -- especially if you are an implementer,
but also if you are a user -- I would encourage you to join the
standards list at OSGeo: