I'm hoping to use Omeka as the CMS for an undergraduate DH/HASTAC course project that draws together historical images, videos, and contemporary GIS data on the ecosystem of a historically significant waterway.
The geolocation plugin seemed ripe for this project, particularly its ability to geolocate the photographs on a map.
I had "expected" the plugin would include some simple KML/KMZ import functionality, something that would enable us to import the scientific data (invasive species, nesting grounds, etc.) collected into the map and to then overlay additional data points marking geolocation of historical images. I'm not finding it. (I do know there's a kml file generated by Omeka, so export to another map is always an option. But that takes a visitor out of the exhibit.)
(I actually thought I'd need to tie the Google map pulled into Omeka to a user-specific G map.)
An alternative, it seems, might involve the ability to embed a Google Custom Map into an item/page in Omeka. This wouldn't put the images and scientific data on a single map, probably, but it might enable us to get the data to display on a navigable Google Map.
Third (worst) option, it seems, is to create map images from the GIS data and to present them as items in a "health of the river" exhibit.
The neatline plugin "may" be a solution/tool, but I'm reluctant to start piling on plugin after plugin without a clear sense that it can get me what I'm looking for.