There's no accounting for taste in this world. As someone who has played both AC09 and DBC, I do understand what Langeveldt means about player skills making more of a difference to how the game unfolds in AC09 compared to DBC. The difference between a good and a bad player was very noticeable in AC09, whereas in DBC it's more subtle, perhaps to a fault.
However, in many other aspects that you can judge a cricket game on, DBC gets the nod from me, and sometimes by a large margin too. Game modes is the big one for me; AC09 is very barebones in this department, with Ashes/Test Series and One-Day/Twenty20 knock-out tournaments being the only non-exhibition modes available. DBC meanwhile has a career mode that might be somewhat lacking in depth, but is nonetheless a great game mode and an important feature for a modern sports game. There's also plenty more competition options and permutations available, especially with the customisation options in the game.
As for the game play itself... I think I speak for many people when I say that bowling markers have traditionally made batting far too easy and unrealistic, and AC09 was no exception. In this regard, DBC's no-marker system is not without it's flaws, because I, and probably many others also, still have to pre-meditate strokes against the fast bowlers due to having to begin your stoke early in order to get ideal timing on the game. Despite this, it's still a big step up from what has come before in the cricket game genre, and the only thing I'd change would be to move the timing windows a bit to make playing each ball on merit against the fast bowlers easier.
AC09 did have customisation options but it was somewhat limited. Limited team slots, created players had a skills cap, and no custom competitions or match types either. And for me at least, the AI in AC09 really struggled against a certain type of delivery that I won't outright state in case it ruins the game for others who still play AC09. I haven't found such a killer delivery to bowl to the AI in DBC yet, though they do appear to struggle a bit more against spin than against pace. And overall, besides the sometimes weird shot selection (aka late cuts), and overly cautious running between the wickets, I find the AI in DBC to be a relatively smart entity...
PS: Regarding the ongoing discussions about edges that I've seen on this forum, I find that edges are a frequent occurrence when I'm batting, but uncommon when bowling to the AI. Most of my edges which result in a wicket go straight to the wicket-keeper; catches in the slips are relatively rare, though the gully does take his fair share of thick edges and miscued cut shots. All of this is on the PS3 version btw.