It's hard to say. I was all pumped up to buy a 909 when they came out. When I went and demo'd a 909 D2, it turned out that I hit my 907 D2 further with no real difference in accuracy, so I'm still gaming my 907. You'll just have to wait and hit 'em both.

I think the fitting aspect of the 910s will be really cool.  From what I've read, the fitting experience will be alot better.

I also had the 907 and looked at the 909D2 but I did make the change because of the fitting to the VooDoo shaft. I have more carry and occasionally more distance but many more fairways. I would hit them all and all of the shaft combinations.