President joe biden set to make a big announcement, tomorrow, about what vaccinated people can do this summer. cnn's nick watt has more. >> reporter: tomorrow, the president expected to announce major tweaks to the covid-19 guidance on who can do what, and where. >> certainly, what one can do, outdoors, vis-a-vis masks is going to be one of those recommendations. >> reporter: allowing the vaccinated to go maskless, outside, might be an incentive to get the vaccine. >> because people who have been vaccinated have wanted some reward from this. >> reporter: closing in on one-third of the u.s. pop...