Integrating Magento and WordPress Users

While there are a lot of different solutions for integrating allowing use of Magento Blocks in WordPress or using WordPress functions in Magento, what you are looking for is single login.

It can be done via a WP Plugin:

  1. Mage Enabler. It’s a WP plugin that gives raw access to the Mage object – you can do single login plus access Magento methods within WordPress (pull templates from Magento, display categories, products and checkout from your blog).
  2. Magento WordPress Integration. I haven’t examined this one.

Or via a Magento extension:

  1. FIshPig’s WordPress Customer Synchronisation
  2. Single Sign-On For Magento And WordPress