the driveshaft change was 2009. seadoo seems to change part numbers on their impellers about every year for either no reason or very minor reasons such as minor pitch changes but has no noticeable affect by normal people on a stock engine.
The pitches didn't change from 06-07, both 10/21s. I would bet that the 2007 will work fine on your 2006 and you don't even notice a difference, other than it works like new.
How does it look different?