Yes, I've had this happen with the TWiT app on my 4th gen iPod touch. I haven't tried to watch any live C|net shows on that device. My guess is that it's a bug in iOS 4.3.1 (and maybe 4.3.0). Those updates were released fairly recently.
Live shows on my iPod 4G are starting in portrait mode and there is no way to switch into the landscape mode. Is anyone experiencing this? It was always in landscape mode (as it should), but something changed a couple of weeks ago. It is useless in portrait mode - too small.

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