Puzzle of the week #126

Chess Diagram: 

[Event "Puzzle #126"][Date "2010.07.16"][Result "1-0"][SetUp "1"][FEN "5k2/5p2/2K2P2/p3Q3/1q5p/1P6/P7/8 w - - 0 1"]

Queen endgames are the hardest ones to predict because of their complexity. If Queens are already on the board, there are multiple check moves to consider. If Queens are about to reappear for both sides as a result of pawn promotions, you can stop too soon in your analysis and come up with the wrong conclusion; this actually happened with a couple of answers I got for puzzle #125, answers which were normally wrong and would have ended that endgame in a draw.
This week's puzzle is another end of the game, but this time between 2 Grand Masters of today. It is white to move. Your tasks:
a) Decide if the game ends in a draw or a win for one of the sides
b) Provide the best line to show your correct decision. Explain your solution

Total available points for this puzzle is 20. The answers will be published next week together with puzzle #127.

Puzzle #125 solution:
I have received some very interesting solutions, but none complete or deep enough. This was actually a very good test to compare your endgame mastery to both players involved: Jacob is rated over 1600 and John is almost 1900. I did not choose any of the answers, but will simply present the correct response.
Black is in perfect position to take advantage of the more advanced pawns it has on the Queen side. This is the correct and fastest winning idea, allowing for two better and one interesting line. I would have given 10 points for the interesting line as well, but nobody got near this idea! After missing lines 1 and 2 John played the endgame extremely well. See solution.

[Event "Puzzle #125"][Date "2010.07.09"][Result "0-1"][SetUp "1"][FEN "8/4p3/2n5/ppB4K/7p/Pk6/5PP1/8 b - - 0 34"]{Game line} 34...Kc4 ({First better line} 34...h3! 35.gxh3 a4 36.h4 b4 37.axb4 a3 38.b5 a2 39.bxc6 a1=Q {Black wins}) ({Second better line} 34...a4! 35.Kxh4 b4 36.axb4 a3 37.b5 a2 38.bxc6 a1=Q {Black wins}) 35.Be3 b4 36.axb4 axb4 37.Kxh4 Kc3 38.g4 Nd4 ({Interesting line} 38...Kc2 39.g5? (39.Bc5! b3 40.Ba3 Ne5 41.g5 Nc4 42.g6 Nxa3 43.g7 b2 44.g8=Q b1=Q {Possible draw}) 39...b3 40.g6 b2 41.g7 b1=Q 42.g8=R Qh1+ 43.Kg3 Qg1+ {Black wins}) 39.Bc1 Kc2 40.g5 Kxc1 41.g6 Ne6 42.f4 b3 43.f5 b2 44.fxe6 b1=Q 45.Kg5 Qb8 {Black won after a few more moves}

Correct solutions:
Owen - 25 points
Karl - 20 points
Frank - 15 points
Jeffrey - 8 points
Alex - 4 points


Queen endgame complexity