Been a lot of tension over the years between Doug & Daniel as most people in the poker community have watched on Twitter. They are about 15% of the way through their $200/$400 ($40,000-No Limit) 25,000 hand challenge.
$200/$400 NLHE Blinds, otherwise known as $40k No-Limit Hold Em'.
25,000 hands to be played, with the person down money at 12,500 hands given the option to quit at 12,500 hands.
2 tables minimum
3-4 days per week minimum, 2 hour sessions minimum
This blog article goes in more detail than we can comfortably do here:
High Stakes Poker Battle: Doug Polk vs Daniel NegreanuMintDice is also offering users that wish to bet on Daniel Negreanu better than PokerShares odds as seen on this post here:
https://bitcointalksearch.org/topic/m.55658387Otherwise, as stated in the blog post, you can place your own bets on the match either through PokerShares (which also has prop betting on the match) or on the BetFair exchange.
Any discussion about the match or questions all can get posted in this thread. I might also be able to get any reasonable questions I don't know the answer to myself answered by Doug himself as long as it's not too personal