Update(1545ET): A big talking point from today has been security guarantees - with European leaders and the US appearing to be on the same page so far, and of course Zelensky is welcoming this as well. 

As a reminder, the Kremlin has said over and over again that it would never accept Western troops enforcing anything inside Ukraine...

Update(1320ET): President Trump clearly appreciated that Zelensky actually showed up at the White House in a suit, in all black, after the Ukrainian delegation pulled up and quickly was welcomed into the White House.