I didn’t know what to expect from this, but then I read the recap from EW which purposefully kept things vague about “surprise guests” and I had to watch.
It’s brilliant.  Especially if you’ve watched any of the real House of Cards on Netflix with Kevin Spacey.  Jimmy Fallon does an eerily accurate impression of Frank, along with lots of the show’s visual cues and choices for scenes.  You have to watch!  Plus, the “opening credits” sequence with the highly-stylized Midtown Manhattan replacing DC is gorgeous.  Gotta love the inverted NBC logo too!