As per the thread title, YouTube videos aren't playinng in Safari for me either via wifi or 3G.
The play fine in the YouTube app but since YouTube has updated m.youtube.com, I prefer watching through Safari since it's much faster and easier.
This is an example of what I see when loading a video via Safari. Note the line through the "play" button:
I'm using a jailbroken iPhone 4 on OS4.0.1
The play fine in the YouTube app but since YouTube has updated m.youtube.com, I prefer watching through Safari since it's much faster and easier.
This is an example of what I see when loading a video via Safari. Note the line through the "play" button:

I'm using a jailbroken iPhone 4 on OS4.0.1