Help With Membership 1.05 Plugin- Not protecting Posts

Hello,
I'm starting a new site and i'm new to this plugin. I just installed version 1.05 on my wordpress 3.0 blog. I believe I setup the plugin as instructed per the directions.

I've created two levels: Free User and Member

For free users i use a negative rule to block access to the Premium Category.

As a test, I posted a premium post here: http://shortzilla.com/premium/new-short-amazon/

Doesn't seem to be blocking a non-registered user.

Any ideas what's going on here?