Replying to 15" vs. 17" -- Final Decision

So I waited until bothe the 15" and 17" C2D MBP's were available before I ordered it for christmas. With the release of the updated mmbp's my decision is really hard now. The new 15" ers have firewire 800 and a better superdrive now. i will be getting a 160gig hd with whichever model I get and price is not an issue at all. With the features almost identical now (other then a 8x vs 6x superdirve) it basically comes down to screensize vs portability. I will be using this as a desktop replacement at university. I will be taking it to work and to school although not all the time. I may also like to move around the apartment with it. However I love watching movies and this will be my sole dvd player and I will be doing a bit of gaming. I'm so stuck I don't know what to get. How is the 17" for portability? Whats more noticable, the lack of portability in the 17" or the lack of screensize on the 15.4"??? soo lost.