The surprising 8.Bd3, which blocks the d-pawn, was first played by Isidor Gunsberg but recently revived by Daniel Stellwagen, who presented an article on it in "Secrets of Opening Surprises, Volume #9." Nakamura played a nearly flawless game with the line, ending in a neat little move that traps Black's queen nearly in the middle of the board (see diagram below). Not only did this near-miniature secure Nakamura sole possession of the $40,000 first prize, but also (I predict) will bring him $275 more in the "SOS competition," for the best game played with a variation written about in Secrets of Opening Surprises!
There are lots of great resources online for those interested in learning more about the US Chess Championship or this final round game. Here are some links worth exploring:
- Nick DeFirmian, "ICC Chess FM Game of the Day, Round 9: Nakamura - Friedel"
Excellent and detailed GM commentary, practically move by move, directed at a broad range of players. Typically this is by subscription only, but for the US Championship they have made it available for free. Best with Internet Explorer. Follow the links on the left for additional Game of the Day coverage. I especially recommend the commentary on Nakamura's round 7 win over Akobian.
- Dennis Monokroussos, "Hikaru Nakamura, 2009 US Champion"
Monokroussos has also annotated a game each round and this final post on the championship links to notes on Nakamura - Friedel as well as previous posts.
- The St. Louis Chess Club's tournament site
The St. Louis Chess Club is simply gorgeous and doing everything right. Their website embeds video coverage of each round. The last video includes an interview with Nakamura where he comments on the Friedel game.
- ICC's ChessFM Channel on YouTube
Features all of the videos embedded at the tournament site, available in HD.
- Jennifer Shahade, "Nakamura 2009 US Champion"
The USCF offered very good round by round coverage of the news.
- Dylan Loeb McClain, "Nakamura Wins Second US Championship"
News and some annotated games from The New York Times chess blog.
- "Hikaru Nakamura is the US Champion" from ChessBase
Excellent photographs and the PGN file of all games.