If the video is too shaky to apply a blur, then it is too shaky to be uploading anyways. If you have Adobe After Affects or Premiere Pro Cs6, try applying the warp stabilizer effect. It should remove the shaky video (It seems to work at least 90% of the time). You should be able to motion track and apply a blur to the plate(s) after thatThanks! @Demolition, yeah, I'm trying that, but my camera is too shaky lol! I've decided to heir on the side of caution. Only post the vids in which I can blur out the plate!
I would never upload without the blur though. If you notice the top guys in the car video niche all blur their plates, and some even take the plates off the cars before filming. A few of them also bring a logo to tape on top of the plate while they shoot. That would be something to look into next time.
good luck!