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I've always wondered why, if we can send balloons to the upper reaches of our atmosphere why we don't use ballooning as a 1st stage launch platform for reaching space?

This balloon lifted a 3000 pound capsule. To do that required the balloon to be 55 storeys tall and have a surface area of 40 acres. A loaded SpaceX Dragon capsule weighs over eight tons, so you're going to need a balloon at least five times as large.

For practical purposes, however, reaching space means getting into orbit. Getting into orbit isn't about the altitude. It is about the velocity. The ISS orbits at approximately Mach 17. Earth's escape velocity (to reach the Moon, and other planets) is about Mach 37. Top speed for a balloon is Mach 0.4 on a generous day. In other words, not much help.

For sounding rockets, and small suborbital payloads, balloons might work. However, beyond that, balloons are quite impractical.

Am I the only one who thought that idiotic ground controller was going to get him killed?

Joe Kittinger was the only one Felix would talk to.

As of this posting, the event is scheduled to start at 6am MDT (noon UTC if I'm converting correctly) on Tuesday, October 9. The official webpage is http://www.redbullstratos.com/

He will be going at terminal velocity for that altitude, which is (I guess) faster than the speed of sound at a lower level, but not necessarily faster than sound at where he jumps from.

The information here suggests that exceeding the local speed of sound is exactly what they're hoping to achieve:

At about 100,000 feet above sea level, Felix Baumgartner will need to accelerate to about 690 miles per hour* to match the speed of sound, known as Mach 1. Then if he continues to accelerate and surpasses the speed of sound, he'll be "supersonic."

* that's the speed of sound at 100,000 feet - at sea level it's closer to 760mph.

I find it odd that the summary neither links to nor mentions the official project page. Perhaps the author has something against Red Bull (or that it uses MS Silverlight). In any case, this is the Red Bull Stratos project, not the Baumgartner Stratos Project. This is some pretty exciting stuff...Besides being totally bad-ass, Kittinger's original jump paved the way for manned space exploration. It may seem tacky to some, but credit should be given where credit is due, and as Red Bull is the primary sponsor of the project, they deserve to be mentioned.

http://www.redbullstratos.com/