A new feature called 'Free Play Day with Gold' has been spotted by Xbox One users in the dash preview which looks to be a new Xbox Live Gold rewards program which will allow Gold subscribers a free day pass to download and play select games. In the image above which was snapped by an Xbox One user you can clearly see that there is a new option called 'Free Play Day With Gold' which can be found along with the 'Games With Gold' options for this month which are Crimson Dragon and Strike Suit Zero. Interestingly though this option isn't showing up in all regions, Xbox users in the UK will not see this new option and its unclear at this point when it will become available in all regions. Whilst very little is still known about this new prgram at this point, we can safely assume that Gold users will have access to a select game for a day. There is still no official word from Microsoft at this point, however we have contacted Phil Spencer to see if he will shed some light.
Are you sure it's not a option for the Beta Dash users? I'll check when I get home because we are in the Beta Dash Preview Program..