Right time to buy 7D/First DSLR suggestions?

The 7D is a good camera for nature photography with 8 frames per second continuous shooting speed and excellent AF system with 19 cross-type sensors. However the 18-135 lens could be a little limiting depending on what you will be photographing. It is a 3 year old design and I regularly need to remove noise from backgrounds of my nature photos.

Would a 650D/T4i with a 15-85 lens meet your needs?

Cheers, Keith