Ab muscles separate during pregnancy is it bad?

[babyeedoll]

I'm prego & I have very strong ab muscles & I've been told theres a real chance they might seperate, something common during pregnancy. The gyno dr told me its actually not bad if they never reattach because it will look like you have a even bigger six pack? What do people know and or experienced regarding the seperation of the stomach muscles? Is it painful? Does it look good if they stay that way? Problems?