The Belgian organization VIAA (staff members formerly working for Packed) will perform 2 or 3 example uploads of 'typical' GLAM collections to Wikimedia Commons with structured data - in any case probably one collection of a Belgian art museum and one collection of a city archive.
There will be a Wikisource pilot, including digitized books in Punjabi, mentored by Satdeep Gill.
Wikimedia España will upload sets of digitized maps and aerial photographs from the Spanish Instituto Geográfico Nacional with structured data on Commons.
The Swedish National Heritage Board has started working on the project Wikimedia Commons Data Roundtripping. It researches and develops a prototype tool to return improved media metadata (translations, data additions etc.) back from Wikimedia Commons to the source institution. This project builds upon the new functionalities and APIs from Structured Data on Wikimedia Commons
More pilot projects, and more details, will be posted in the upcoming months. All the pilots will lead to new documentation for all Wikimedians and GLAM staff who want to do GLAM batch uploads with structured data on Wikimedia Commons.
First features of Structured Data on Commons going live in January 2019
Multilingual file captions on Wikimedia Commons are the first public feature of Structured Data on Wikimedia Commons. They are released around Thursday, 10 January 2019. Captions are a feature to add short, translatable descriptions to files.
There is a help page for using captions on mediawiki.org (because captions are available for any MediaWiki user). Feel free to contribute to GLAM-related documentation for captions on Wikimedia Commons if a help page becomes available there as well.