The Alternate CD always takes longer to install than the Desktop CD (which is Ubuntu's live CD, by the way - it would make sense to compare the Ubuntu live CD to the Fedora live CD, wouldn't it?).
As I understand it, the Desktop CD has a compressed image of the installation that it just copies over to install, and that's why it takes about 10 minutes (yes, it takes about 10 minutes in Ubuntu, too, if you use the live CD instead of the Alternate one).
The Alternate CD, on the other hand, has the actual packages used for installing and unpacks each one and installs each one individually, which takes a lot longer. The Alternate CD is good for special situations (low RAM, for example). If you want a speedy installation, I don't know why you'd use the Alternate CD.
In any case, why can't humans wait 40 minutes? Imagine the life span (beyond immortality, I guess) of all those Windows users who took literally hours, if not days to get Windows installed.