For fun I played around this afternoon. I opened Windows Task Manager and checked the BT CPU usage on the Q6600 as I viewed different tabs and computers. I found some interesting behavior. Note that 25 is one CPU on a quad.
Q6600/Win Vista (BT host): BT minimized 0-2, viewing Q6600 BOINC tasks 25, viewing Q6600 transfers 4-8. Other tabs show 4-8 as well. Well, this is interesting

Looking at 7 remote hosts (all tabs): 4-8 (on Q6600 CPU) except viewing AMD Phenom II X4 955/Win 7. This AMD host shows the same behavior as the Q6600; 25 viewing tasks, 4-8 otherwise. The Q6600 and the AMD Phenom are my 2 fastest computers. They also have the largest number of tasks; 137 and 210 respectively.
I offer this as an observation hoping someone will have an "ah ha!" moment and will know exactly what's happening. I just find it strange
