Hmm..
Well logic would dictate you would do a dry run free test first to make sure you've got your shit covered.
The second best thing would be to estimate high for bandwidth (which is almost certainly the problem - buffering).
The worst is to do what they've done. Take your money and hope it works 
Come on.. you all saw this coming.
Whoever came up with this idea should be thrown off a bridge with a chain tied to his testicles....
If you got exclusive rights to HBO boxing or something, and decided to put it on Webcsast instead of T.V., HBO would not only kill you for proposing such a stupid idea, but hunt down everyone you're related to and know personally; and throw acid in their eyes and punch them in the throat repeatedly as they gasped for air.
In other words....this webcast olympia is the gayest thing since Clay Aiken