Standard functionality. You can embed the related iframe code through the editor. Also you can upload and select images...try the demos yourself (plone-demo.info)
There is a default 404 page with a list of alternative content options...should be easy to customize this with a custom template (z3c.jbot or so)
No idea what this exactly means. Adding geo coordinates to content-types is possibly doing a behavior like collective.geolocationbehavior.