Google has revamped and redesigned the structured data testing tool. It now looks more friendly but adding this simplistic overlay box that either asks for the URL you want to test or a snippet of sample code.
When you plug it in, Google will show you if you validate or not. If you do not, you will need to click to see each type of schema and the errors for each. I believe this is instead of Google showing you all the errors for all the various schemas you have on a single page all at once. Now you need to click into each one by using the arrows to see the errors specific to that schema.
This was releases Thursday night/Friday morning, and I received tons of emails and notifications since from you all about it. So thank you all.
John Mueller of Google confirmed on Google+ this is new.
