Jennie from the YouTube team posted in the YouTube Help forums that the YouTube Capture app that is currently live is uploading videos upside down.
This seems to be a specific bug to version version 1.4, which is live right now in the App Store.
Google's solution to the bug? Turn your phone upside down or use the flip feature in YouTube enhancements. I kid you not.
Here is Jennie's response:
We're experiencing a temporary issue with YouTube Capture v.1.4 where videos shot with the record button on the left appear upside down. To fix this, you can rotate your video with YouTube Enhancements.
My next search video may be upside down for you.
Forum discussion at YouTube Help.
