updating octree's or similar data structures

[lhkbob]

This can be relevant to graphics object culling as well as collision detection, but for my current purpose, I'm planning on using an octree or similar to speed up the calculations to determine which bots are in a line of sight.  My question is, are there any optimized methods/algorithms to efficiently update the octree since each bot is capable of moving? 

Or, perhaps there is another way of organizing the bots that could be even faster.  The reason, though, that I'm choosing octree for the moment, is that it's probably going to be the same structure that I'm using for graphics and physics, so I could link them together and only have to perform the moving object updates once.

Thanks,