This is just a fun question that you used to be able to easily answer on youtube. But it seems some time in Nov 09 it was removed. but while it seems to be gone there still seems to be a way to access the number for the time being.
- go here: http://gdata.youtube.com/feeds/api/users/USERNAME?v=2 and replace USERNAME with your username
- Search for videoWatchCount
kind of a pain but hopefully that data will stay in the feed. We know google is tracking us all very closely. we might as well have access to that data.