Just Map It! for WordPress plugin is provided by Social Computing. It enables the visualization of your blog posts as an interactive map.
An interactive map should appear at the bottom of each blog post when the option is checked. This map shows the relations between the post being read and other blog posts by the tags they share.
The map will not be rendered until the Just Map It! client is installed. Go to the plugin settings page and check that the Just Map It! client is sucessfully installed and that no additional step is required.
The white page you see when you click on the download link appears because your browser tries to open the flash client instead of offering to download it. Which means the link is valid but you don't have a download dialog box. After clicking on the link, when you see the white page, you can save the .swf file by clicking on your browser's menu and selecting the "save as..." entry. Or you can right click on the download link and select "save link as ..." to start to download the remote flash client.