There is a lot that came out of Where 2.0 and Wherecamp that directly affects this discussion and I’ve been doing my best to digest it all.  Here are some of the highlights:
Google

Flash API for Maps
Feature/Layer Enhancements to Google Maps (Real Estate, Photos, Wikipedia, et al)
Google Friend Connect
REST-based API for GeoSearch

Yahoo
Yahoo Internet Location Platform

Placebase/Pushpin
Free REST-based [...]

BURLINGAME, California — The Openlocation.org initiative launches officially today at the O’Reilly Where 2.0 Conference.
Location technology is driving the current wave of innovation on the web.  With location capability in converged platforms like iPhone, Blackberry, and Android, location will become a vital part of how we find and use information.
Until now, location-based services have focused [...]

As of this morning, Google has announced a new Geosearch API that can be programatically accessed rather than just accessed visually (via Google Maps or Google Earth).
However, it seems that this API can only be accessed using their Javascript browser-based API, which renders this API less than useful for most server-side applications. Without any insight [...]

This collection of Android Apps out of MIT exemplifies the kind of “location is the new oxygen” thinking that I think will pervade the coming SocialMobileGeo web. More about these on Yahoo.
Goes to show you that these ideas can be created and implemented in a lightweight, fun, playful way and that it doesn’t require a venture [...]