When Destiny 2 was announced, the PC version didn't have a hard date on release. All we heard was it was coming later than the console versions being released on September 6th. Well, now we know.
Bungie has tweeted out that October 24th, a month and change after the console release, is when PC players will be able to join in. Not only that, but they also let loose the BETA release dates as well.
July 18th is when PS4 pre-order folks can play the BETA. The day after, July 19th, Xbox One players will be able to participate. Anyone can play on July 21st. July 23rd is the day the BETA closes. PC players can play the BETA sometime in August.
So there ya go. Everything is now set for what should be one of the best selling games of 2017.