Today Google announced a new opt-in program that allows webmaster to live preview changes to the Google +1 button before they go live (Google’s official blog post). After you’ve enrolled in the program, you will begin to see updates and changes to the Google +1 button on sites across the Internet, even though those changes are not yet visible to the general public.

The first demonstration of the new preview was also announced today. Google is testing hover text that will come up when a user positions her mouse over a +1 button. Before clicking, the hover text reminds the user that clicking the button will publicly +1 the page or site, and show the account that will be associated with this +1.

Plus 1 Preview Demo

Hovering over a +1 button before clicking

After a visitor clicks a +1 button, the hover text changes to remind the user that he +1’ed the page and with what account:

Plus 1 preview demo post click

Hovering over a +1 button after clicking

Click here to sign up for the Google +1 Button preview program