UPDATE: As of 10:37 P.M. (EDT) Apple pulled MiTube from the AppStore (no surprise) it was live for about 4 hours (better than the flashlight/free tethering app!) So I hope you guys got it. I would do a review but so few people have it it would be pointless. Just a quick update and I hope you got it! I was also pretty close on guessing it would be taken off by tomorrow, it lasted until 11:00 P.M. so pretty close.
This is one of those apps that might not be in the App Store tomorrow. MiTube lets you download MP4s of YouTube videos to save on your iOS device. Get it ASAP Apple will take it down tomorrow most likely.
MxTube has been a Cydia app for awhile but for whatever reason Apple approved it. Get it while you can.