Update (1820ET): President Trump is still reportedly up by hundreds of thousands of votes in PA, but as more absentee ballots are opened his lead appears to be shrinking. With Biden winning some key calls in Michigan and Nevada (calls that, notably, don't reflect final vote tallies), his campaign has decided to launch its transition team website, adopting what one might call a "fake it 'till you make it" approach to the presidency.
Biden's team has been planning for months for the possibility that the Trump administration won't cooperate with his aides, and deliberately try to stonewall him, breaking years of tradition when it comes to presidential transfer of power.
"The crises facing the country are severe—from a pandemic to an economic recession, climate change to racial injustice—and the transition team will continue preparing at full speed so that the Biden-Harris Administration can hit the ground running on Day One," a transition official said, echoing a statement on the transition team's newly launched website.
As officials prepare to count votes for a third day, Fox News is calling Trump ahead in Georgia, while the NYT is saying that Biden may have squeaked ahead after appearing to take Michigan, Wisconsin (two of the three "blue wall" states) along with Nevada. Still, the final vote tallies aren't yet in, and as we saw with Arizona, early calls risk embarrassing reversals later on.