I dont think the Stampede will impact the Bash or vice versa. I think with the economy the way it is, folks will start seeing more and more localized or regional events and take one or *maybe* two big trips during the year. I have been to most of the Bash events, since the first and while its a great time, if it really came down to picking one vs the other, I'd probably go west to experience something new if finances/work allow it.
I know there is an event in the works for the NE area, again not being planned for something to compete with the bash or the Stampede, but something more regional for folks that cant make it to one of the big events at a time that should not draw folks from any other event.
The Stampede sounds like a whole pile of fun so far, so keep up the good work... I know how hard planning these things can be