UPDATE July 24, 2012 So I have created a dev V2 of the plugin. Completely rewritten from the ground up. You can download and test it at: https://github.com/matthewaprice/WP-Export-Users It now makes a download file automatically. No longer just displays the results in a textarea. I also removed the field encapsulators and separators as I modified how the file is made. The resulting file is openable directly with Excel or Pages ( it is a CSV file ).
I am working on the import feature and will have that up in the next couple of days as well as other features Matt --- This is a nifty little plugin that allows you to customize CSV output of your users. It will export their username, display name, and email address. You can select which columns you need and then review the output from the admin area. You can regenerate the output as many times as you like then copy and paste the data either into a text file or directly into the system that it needs to go. For example, you have your newsletter hosted by Constant Contact, Moible Storm, iContact, etc. They have very easy import options for CSV files or some have a "Copy and Paste" your data directly into the system. Some of these API's even cost money. So you can use this plugin to craft the data how you want/the other systems, want. You can download the plugin at: http://wordpress.org/extend/plugins/wp-export-users/