Implement report tooltip ability
As per October '18 update support for report tooltips in custom visuals is generally available. link
As a starting point, this seems like a good reference how to implement this: Add canvas tooltips support to sampleBarChart (#35)
I second this. Here's a mockup where the report tooltip shows a place's photo. (That tooltip is actually from the table to the right of the map, but this shows the purpose and look & feel).

I'll take a look at adding this to beta-1.4, looks like a simple change, and I'd love to have report in tooltip support!
Attempted to implement this in beta 1.4 - I was able to enable the custom tooltip in the UI for the Mapbox Visual, but not get the tooltip injected with the custom report from another page. I'll push my attempt to a PR for later reference. Pushing to v1.5 cc/ @samgehret
This page might help. Report tooltips work in Maq's KPIColumn (I tested it), here's the related commit for reference: https://github.com/maqsoftware/PowerBI-visuals/pull/339
Thanks for the reference code, @otravers!
Could you please provide an update on the report tool tips? I'm using a mapbox product in my PowerBI dashboard and my client is requesting report page tool tips. It would be great to know if this feature will be available soon!