Matt's baby is great - he has "touch and go" power, as Hiro puts it, and he can use it to turn on television or Hiro's lost power over time. The scenes with Hiro, Ando, and Matt's baby were one of the best in the series, crackling with great one-liners from Hiro, along the lines of "heroes are supposed to change the world, not diapers".
And in another well-played family moment, Tracy meets her nephew, Mica - who turns out to be Rebel. A very nice touch. Mica makes Tracy see that being out for only herself is not the way to go, and she sacrifices herself to save Rebel. Her ice-self is shot point blank by Danko (Željko Ivanek - he of at least four current or very recent series, Heroes, Big Love, True Blood, and, last year, Damages). But she winks after being shattered - and there's always the third sister - so, one way or another, we'll be seeing more of Ali Larter on Heroes, which is all to the good.
But the denouement of 3.20 is sad. Daphne is rescued, seems to recover from her wound, and parts with Matt. But that's not the sad part. He goes after her. Tells her he can fly ... shows her. But she realizes Matt has put this story in her head as a way of making her last minutes happy. In reality, she dies.
But this was a great if sad way of ending their story, and Heroes continues to carve out a deeper groove in our emotions and imaginations.
See also Heroes Gets Lost ... Heroes 3 Begins: Best Yet, Riddled with Time Travel and Paradox ... Sylar's Redemption and other Heroes and Villains Mergers ... Costa Nuclear ... Hearts of Gold and the Debased ... Seeing the Future Trumps Time Travel ... Superpowered Chess with Shifting Pieces ... Villains and Backstories ... The Redemption of Sylar ... Thoughts on the Eclipse, Part I ... The Lore of the Comic Book Store ... Hiro's Time Traveling Closure ... Augmented ... Shades of Recalibration