yPHPlista integrates your PHPList install with beautiful AJAX.
yPHPlista is a new plugin I wrote because I was unsatisfied with current ones integrating phplist with wordpress. this plugin does it best, and it does it with style. both ajax ("same page") signup and gracefully degrading JS so your users can visit their normal subscription page.
For more information visit http://social-ink.net or http://www.social-ink.net/blog/yphplista-an-ajax-wordpress-plugin-for-phplist-integration
Please note, as with every plugin or theme modification, you should do a backup of your files beforehand. Although we've tested this across many installs, we are not responsible for anything it does to your system and do not guarantee support.