I am in the market for a new PB with the SuperDrive and I am looking forward to using iDVD for the first time. My question is how much HD space will I need to fill a DVDs. I would mostly be compiling collections of short home movies (10-20min max) onto a single DVD. To do this do I have to have enough space on my HD for a 2 hour DV stream? What is the ratio DV stream to HD space? I know I should get as large a hard drive as possible but I am limitied by budget and I already need to get other extras like RAM and Airport Card. Thanks for the help.