"Geotaggable" is a user-friendly application that enables geotagging with ease. It is compatible with Apple's Aperture and Google Earth, making location-based image searching a breeze.
While there are a few small kinks that need to be worked out - 'Make KMZ' isn't currently functional and the next/previous buttons may act up while in floating mode - the developers of GPS2Aperture Lite have big plans for the future. They intend to keep the Lite version completely free, while creating a paid version that can geotag from GPS log files with the same visual aid of Google Earth. If you're looking for something even more feature-rich, the paid version will be available as part of Aperture Assistant, but also sold as a standalone product at a lower price point.
Version 1.0.26 Beta: N/A