With 2D things are a little tricky to break down between 900mhz 2g and 900mhz 3g. Basically there is no way to tell for sure but pretty much non-AKL/WEL/CHC/QTN sites have 900mhz 3g.
As for Dual Channel, there's no way to tell from the radio licence info. They have applied for license to use both of their 5mhz channels at all sites, so thats no help.
I believe 2D did a HSPA+ rollout last year to give their sites a speed boost upto 21mbps but as to how extensively this was rolled out I have no idea. Logic would suggest doing this in the densest locations first, ie cities.
I applaud 2d if they do upgrade their original 4 cities to 900mhz 3g. This is why XT still wins for being the best network as XT has complete (100% sites) 850mhz 3g coverage even in cities where 2d/voda are using 2100mhz 3g.