hey everyone,
So a fun little google search on this topic turns up my prior complaints with google's complete inability to successfully provide the following functionality:
1- Assign nodes a location (address turned into lat/lan)
2- Be able to display all the nodes on a views map
3- Be able to search by proximity.
Locations and Gamp are supposed to handle this, but of course they don't, and result in all kinds of lame errors and it just doesn't work out. The errors and difficulty getting this to work were quite plentiful.
Enter openlayers, drupals new and oh so fancy method for making this work. Okay, I can get the points on a map, I can get things work... but I get one hell of a fun error when I enable openlayers_proximity (which is in early dev, but it's definitely not working).
So who has a working drupal 6 solution for mapping? This is ungodly simple functionality that's been handled a billion different ways, and yet it doesn't exist yet functionally in drupal?

Comments
There are plenty of good examples - here's a few of ours.
http://saveourgulf.org/observations - Mapstraction and Geo modules at play. (Click a point and then view the "nearby" tab to see simple proximity search between points, supported fragilely by Geo module)
http://muddywaterwatch.org/monitoring/maps - Location and GMaps modules. Proximity search works, as long as you don't enter a proximity greater than 999 miles.
http://map.jrava.org - Open Layers (and a bunch of contribs). No proximity search, but plenty of fun.
Mapping in Drupal certainly isn't /simple/. But it's far from an achilles heel or an armpit. Proximity search isn't particularly strong b/c Drupal doesn't handle native Geo data types in the DB. But finding distances between individual points is just a bit of trig, which can be done fairly well.
Good luck!
Sean Larkin
ThinkShout.com