Hi all, the AppleTV upgrade was enough to sell me on giving this try. What I haven't been able to figure out, despite pouring through these Forums, is why exactly would one choose the 160 over the 40, or vice-versa. Everything else is the same, just a bigger hard drive. If the AppleTV streams everything from your computer....and deletes the movie rentals when they are done, why would one need such a large hard drive. I hate to cripple my purchase and am willing to spend the extra money if necessary for the bigger drive, but I'm not sure why I would need it. The AppleTV would sync everything you purchase on it back to your main computer's iTunes, correct...so what am I missing here. If I was using it with the new software update as a standalone, without a separate main computer in the house I can understand it, but otherwise...? Can someone here please enlighten me so I can make the correct purchase this week. Thank you so much.