ablancodev

Synchronizes wordpress users with MailChimp. Select MailChimp list, group and subgroup (subscribers organized in a subgroup or according to your role), and automatically new users are added to this mailchimp group. 
Add, update and delete synchronized users.
Official site: <a href="http://eggemplo.com/plugins/users2mailchimp/" rel="nofollow ugc">eggemplo</a>

Users2MailChimp

Synchronizes wordpress users with MailChimp email marketing service.

chherbst

This plugin synchronizes information of an Semantic Media Wiki 
with a wordpress blog.
It is supposed to be used in production without any downtime of the site. 
The way SMW data is imported can be configured using a simple php mapping array.
Until now it supports importing poss, categories, attachments, meta data, links and full galleries. Only data which has actually changed will be imported, thus minimizing the 
time on successive imports.
The supported import format is JSON. Thus it could also be used for data sources other than Semantic Media Wikis, as long as they export their data in JSON format.

SMW Import

Plugin to synchronize a wordpress blog with a JSON source, e.g. a Semantic Media Wiki.

Users2MailChimp vs SMW Import