What do people prefer - open-plan kitchen diner thing with doors into a living room or separate rooms?

[Tinker]

Spotted open-plan a few times on the list of things people hate about their houses. Our kitchen is too small and needs to be extended. I'd hoped to combine it with extending teh dining room and making them in to a big kitchen-diner.

Good idead or bad idea?

good idea. I don't like total open plan but kitchen diner is a must for me.