Plan the meeting agenda ahead of time
Working with people in different continents means brainstorming with them too. That means 10 people will have different pieces of information, 10 will have ideas based on them. A single person can "plan" ahead only as much as his own information. This being 10% of the total information, ideas generated by himself would need to be seriously modified even if useful by themselves. This modification needs to be communicated fast and effectively - even while being bombarded by 9 others giving extra information and giving their own original and modified ideas.
The above might seem more chaotic than it needs to be, but it is definitely something for which "planning" gets dwarfed.
With 10 people in the same room, an effective brainstorming session can be produced. Something about the virtual central shared whiteboard hampers it.