Hello, I run a site that is currently built of 3 components,
OSCommerce, vBulletin, and WordPress.
I'm using WordPress to run my site's articles, and front page news updates. Users are encouraged to join discussions on vBulletin. The site also runs a e-commerce store using oscommerce.
Right now, all three systems require a different logins.
It keeps it simple, and also secure, but it also leads to some confusion and usability issues.
I have looked into this a little, and doing the vBulletin integration is the hardest due to the commercial nature of the software and such.
I just wanted to hear opinions for or against unified login.