« on: March 13, 2012, 10:01:26 AM »
well, in landscapes and buildings (where you focus manually on your tripod using live view and low ISOs), you wouldn't see that much improvement. In night photography (where you use AF, high ISOs, fast shutter speeds and fast prime lenses) you could see great improvement on the AF performance and noise if you went for the 5D mark III.
I'm just guessing here as i don't know exactly how you like to shoot.
Personally I would buy photoshop CS5 (if you don't have it already), some fun filters and a vertical grip. I would also sell the 18-55 and probably the 18-200 and buy the EF-S 15-85. ( I would probably also sell the 10-22, but that's just me, i don't do much of ultra wide angle and the 15mm would be plenty wide for my shooting preferences)
The biggest reason why i would upgrade to 5D is that i would get the full advantage from those primes and get shallower DOF more easily. Then again, i would save money and go for 5D mark II (and with the money I save i would get a 85mm prime.)