Which is sorta big news because over the past couple of years there has been a bit of a mass exodus of writers from Valve - well, those who were involved in the narrative experiences we've come to associate with the studio. Where Erik Wolpaw and Chet Faliszek left the studio last year alongside Portal 2 co-writer Jay Pinkerton - who has since returned.
And when you boil it down to the simple logic question of "What does a story and narrative game writer do at Valve?" The answer to that of course is write. Pinketron, who also wrote Team Fortress 2 comics in addition to Left 4 Dead and Left 4 Dead 2 material left the studio mid-2017. As to whether or not his return has anything to do with the several games currently in development at Valve we can only speculate.