Jeff Yutzler first presented the information in the presentation. This was followed by discussion among the participants. Some key points from that discussion:
GeoPackage fits between GeoJSON, which is very lightweight and text based, and a full-blown spatial database system.
GeoPackage is broadly implemented - there are 10-15 vendors listed on the GeoPackage.org site.
GeoPackage is meant to be lightweight enough for mobile applications. It's possible to package changes to a previous file into a new file and apply those changes to the device, but actual synchronization is not a current feature of the spec or of any extensions, but it could be possible in the future.
Shapefiles can only contain one geometry type per file.
GeoPackage can currently handle integer data for images (JPG and PNG). An extension to handle floating point is in the works. A Tile Gridded Coverage extension that used 256x256 TIFF files is being considered. A public comment period should be starting in August.
There are practical limits to the amount of data that can be put into a GeoPackage file. However, hydrology for the Mississippi river would fit very comfortably
When thinking about limits to GeoPackage, realize that most of those limits (and more) apply to Shapefiles.