It\'s been a while since iPhone 3GS came out, and now there might be enough market share of OpenGL ES 2.0 supporting devices to warrant developing in it.
Bu
If you have existing projects, I wouldn't recommend moving to 2.0, considering the effort required is very likely more than it'd be worth. That said, for any new projects, there's no reason to even bother to consider 1.1 anymore in my opinion. Most of the devices that have been sold are 3GS' or 4s, both of which are more than capable of handling 2.0.