After hours of testing, I am positive that the v1.6 has created a new bug for Tier Pricing.
One of the post here regarding the issue.
I was working on two new sites in version 1.6, both are freshly installed, use no Simple Data, and I have added Tier Pricing for Simple and Configurable products, and all are not showing up in the frontend.
Before attempting to file a bug report, I ran two more tests by installing new stores, one uses Simple Data (Store A) and one without (Store B). I changed nothing to these two stores as far as skin and theme concern.
WIth Store A I can see the Tier pricing shows up fine with the product from Simple Data installed; but Tier pricing doesn’t show up when I added new product.
WIth Store B , same story, Tier pricing doesn’t shows.