the fit of the iPod Touch into their sound dock.

You may also want to consider that those songs, video's and tv shows may not actually be yours to give away or sell.

If they are all in iTunes, for instance, on your computer and will be making their way onto your new iPod Touch then there would be some that would say that you sold them illegally. As in, you did not own the rights to sell them.
Now I guess you could give them away with your old ipod and remove them from your computer and still be legal. I not so sure that their being on the iPod actually increased its value and I would not publicly announce that it was a selling point.

There was a company that was selling pre-loaded iPods but soon got a cease and desist order from the music's copyright owners.

P