I can be pretty simple with an array of still cameras (The Matrix) and played through with flash. Vegas can be used to compose the sequence as a video file, but for the interactivity you would want to use flash. Seems like it would be a lot of work.
Yup just get about 30-50 still digital cams all set at the exact same settings and white balance, line them up in array...and well it gets pretty complicated.
Do a search on the internet for "Bullet time" like Rob said .