[jessedhillon]

If you are doing analysis and exploration, or creating offline reports, QGIS is worth learning. It can connect to and query a PostGIS backend directly, and doesn't need to do any sort of intermediate translation and storage that I've seen other packages require. It's scriptable, and extremely flexible -- I've used it to create reports and artifacts to share externally. Overall a solid example of spectacular open source software.

[billfruit]

While QGIS is ok, for many applications including analysis and making reports. It is not particularly suited if you want to embed a map view in another application, or to build a full custom front end to render map views.