Zickzack: This game has got a lot of coverage in German chess books. The combination starting with 19. Rg7: is so long and beautiful that it might even be a composed game.
Most analytics agree on that Black plays a passive defence, wastes time capturing pawns, and gets crushed deservedly. Morphy redivivus. <Pachman> for instance says that White's pawn sacrifice 13. b4 is more impressive than a Queen sacrifice leading to a forced mate.
Fritz10 disagrees. According to it, White has the better position after the 12th move. The pawn sacrifices leave Black with a defendable position, as his Queen is not out of play (Nimzowitsch comes to mind, because he played like this more than once). So, White should have played 13. Bb4 or 13. Bh4.
Black's defence crumbles after 17. ... Qd6. Instead, 17. ... Bc5 might hold the game: 18. Bb4 b6, 19. c4 Qd8, 20. Bc5: bc:, 21. Rc5: a5 with an equal position.