How have you guys dealt with batching workflows.

Lets say I have 10,000 talks that all need to get set to complete. the way I've been doing it is creating an event for each task then applying that event to the aggregate..1...by....1. performance really takes a hit.

Is there a pattern to apply thousands of events in one go to save database round trips and speed this whole thing up? This seems like a subject that needs to be covered in more detail. Any suggestions?