The home store sells new style corner bead that is plastic and rounded that muds to the drywall...............

I just came across this thread and wanted to add that if you're looking for a larger radius, such as 9" or greater, you'll need to use bending plywood over "ribs" that create the corner and span the distance between the two 90 degree walls. Pick up the "Framing Floors, Walls, and Ceilings" edition of the "For Pros By Pros" series for a better description.

are you talking about bullnose carner beads?

I'm not talking about trim molding, if that's what you mean. I was referring to a curved corner, a change in the framing of the wall intersection in order to facilitate a large-radius turn that spans the 90 degrees from wall to wall.

Then thats done with the framing and two layers of 1/4 inch drywall

Well, in the book it's done how I described.

If it is a real tight round corner they just do it by standing the studs close and making the radius.

As a Painter for the past 5 years I just come across my first new construction with drywall rounded corners...

Stupidiest idea yet.. for example where a hallway that is mocha meets lets say a dinning room that is off white.. There isnt a Natrual stop... doesnt matter ive tried laser levels and tape etc.. looks retarded

RockinRob, I know your post was quite a while ago but if you haven't solved your problem with painting rounded corners yet, I found a great tool, the BlendMate. It blends the two wall colors at the rounded corner! It looks amazing (not retarded!) I got mine online - I haven't seen it in any stores.