Do modern engines need running in?

[DartyBistard]

Curious to know what people's thoughts on this are. I know the temptation when you get a new car is to see what it'll do right from the jump, but do modern engines really require running in like old engines?

I'd have thought that nowadays modern lubricants and machining techniques mean that if the engine is up to temp then rag away to your hearts content, regardless of how new it is....