I made it official the other day and set the status of the OpenLayers module to "Needs New Maintainer". It was on "Looking for Co-Maintainer", but I just can't seem to find the time to put towards the module anymore and don't want to give people false expectations. It is a bit sad, but my work on the module has almost all been in my own free time, and the focus of my professional work is moving away from Drupal (though not completely).
I wish there was some serious investment in this module and other mapping modules (well maybe just mapping modules). Given this statement, this means there is no good, future-proof mapping module for Drupal currently. There are some great potentials, and OpenLayers module is pretty good and the most comprehensive, but it is not good enough, especially without a maintainer. I think Leaflet is the best library option at the moment (though I wouldn't put all my money on it), but the Leaflet module is pretty basic at the moment. GMap has been self-proclaimed legacy, and needs a bit of a reset to becoming a strong, innovative mapping solution for Drupal again. The Mapping module that I started, I think, is a good direction to go for Drupal as web-based, slippy maps have most of the same components, but I have not had the time to build that out in a serious way. The OpenLayers library is still a staple in the web mapping space, but it needs some serious improvements to become something really useful for everyone (and there is work going on to improvement it). Modest Maps is a good library, but as the name suggests, it is very minimal which means that extending it would be a significant part of any Drupal integration.
I just wanted to post this in this group to help get the word out and maybe spark someone's interest in becoming a maintainer, and also to just write a little about the state of mapping in Drupal (which is in a bit of a lull).