I think in your own home then any amount of presents which are appropriate but in anyone else's home, then one present. If it's the DGC then one bigger present than multiple ones. Like you say, Collearn, they just get bored opening them all anyway. My DGC opened theirs and cards and threw them on the floor and walked on them.
Just heard about the 4 Christmas present suggestion on the news: something they want, something to wear, something they need, something to read. Think it's a great idea. My DGCs get far too much. There are seven of them and last year's rip, glance, chuck fest irritated a few of us. I've cut down on what I'm buying them this year, partly because the whole Christmas thing's out of control and partly because I can't afford the things they want anyway. What does everybody else think?