Leander Kahney:
As our friend Chris Foresman of Ars Technica fame points out in the comments, 3G tops out at a paltry 64Kbps. ” It looks like crap on the iPhone,” says Chris, “so it shouldn’t be a surprise that it looks like crap 4x as big?”
I don’t have a 3G iPad but based on what I have seen on the iPhone I believe it. Also I can confirm this to be true as well:
Meanwhile, our readers are reporting that Verizon’s MiFi delivers: there’s no difference in quality between Wi-Fi and 3G on Verizon’s network.
It appears to effect other iPad apps that stream video as well.