The DCC can't change any dates now as everyone has made their hotel and travel reservations already. For 2010, it is what it is. Also, I don't think that most pros play in the banks and one pocket only because of the 'Master of the Table' prize money. That's an incentive for sure, but there are pretty high payouts for banks and one pocket by themselves, so I assume they're playing in those to actually try and win and make more money.
Also, as for the list of players thrown out there so far who won't be attending, Niels, Ralf, Mika and SVB have all won the 9-ball event at the DCC at least once (Ralf has won it 3 times). Other than that, I believe no one mentioned yet has placed 1st or 2nd in the banks at DCC ever, and only Corey has placed in the one pocket event and that was 2nd place back in 2004. So, no, the overall caliber of players will not be hurt that much. The 9-ball will suffer a bit, and not having SVB will hurt the action a little, but there is SO much action at the DCC, I can't see one big action player not showing making the difference.
Once again, if you ask the pros, I'm sure they would have preferred being able to play fully in both events, as it would mean more money for them. As for how much money, just look below for an idea of how pissed the pros should be if they can't play in both events. For example, if SVB's team doesn't win the WTC 2010, he would actually make less money (much less) than he did this year at the DCC (of course, he could also flop at the DCC 2010, but this is just an example). Also, Brumback won more than $30k last year at the DCC, which is more than the 1st place team at the WTC 2010 will make per player. From only placing 3rd in the 9-ball and 2nd in the 10-ball last year, Ralf made $9k, which means his team has to place 1st or 2nd at the WTC 2010 for him to make money at WTC 2010 than he did at the DCC 2009. Of course, the WTC 2010 is payouts/player and it's always nice to see high payouts, but these are just some numbers to consider.
Payouts from the DCC 2009
9-ball
1st place Shane Van Boening $16,000.00
2nd place Lee Vann Corteza $8,000.00
3rd place Ralf Souquet $4,000.00
3rd place Adam Smith $4,000.00
One pocket
1st place John Schmidt $12,000.00
2nd place Scott Frost $6,000.00
3rd place Jose Parica $2,700.00
3rd place Jeremy Jones $2,700.00
Banks
1st place John Brumback $10,000.00
2nd place Rodolfo Luat $5,000.00
3rd place Jonathan Hennessee $2,500.00
4th place Brian Gregg $1,450.00
Master of the Table
1st place John Brumback $20,000.00
2nd place Jonathan Hennessee $3,000.00
3rd place Shane Van Boening $2,000.00
10-ball challenge
1st place Lee Vann Corteza $10,000.00
2nd place Ralf Souquet $5,000.00
3rd place Mika Immonen $2,500.00
4th place Francisco Bustamante $2,500.00
Straight pool challenge
1st place Danny Harriman $2,500.00
2nd place John Schmidt $2,400.00
3rd place Darren Appleton $2,000.00
4th place Thorsten Hohmann $1,400.00