If we're talking about kids parties I think it depends on the situation. For Moo's first birthday we were in a hall with stacks of other kids. So we took them home and unwrapped them the next day. This was because we didn't want anything getting lost or broken. But his second birthday was just a low key thing at home with family, only kids were 3 of his cousins. So we felt quite okay with Moo opening his pressies as his guests arrived, nothing was going to get accidently thrown out etc.
I've been at parties where the kids pressies have been opened and then all the kids are playing with it and bits are going everywhere...I'm always worried they're going to lose crucial pieces :lol:
No matter when the gifts get opened I always send out a personal thankyou card so hopefully the giver can see how much it is appreciated and enjoyed anyway.

