for the same price as ipod, you can get stuff from Archos that will also play video, and is usually bigger.
who needs 40GB? depends how you use it. if you use it as a portable hard disk to store all your mp3's on, even 40GB is not enough. and if you got plenty of videos on it too....
the samller ones are all well and good, but you've got to keep plugging it in to you pc to reload stuff on it, or you'll soon get bored of listening to the same thing over and over.