Welcome to the new generation of Mac OS X, where that old downloads page from Apple is now nonexistent. Apple has now changed the page to display information about their new Mac App Store.
Apple emailed their developers last December with the reason that they have taken the page down, it describes how they believe it is a step forward towards the unification of iOS and the Mac. Here is what the email said:
Because we believe the Mac App Store will be the best destination for users to discover, purchase, and download your apps, we will no longer offer apps on the Mac OS X Downloads site. Instead, beginning January 6, we will be directing users to explore the range of apps available on the Mac App Store.
We appreciate your support of the Mac platform and hope you’ll take advantage of this new opportunity to showcase your apps to even more users.
MacStories notes that the Widgets page is still available here. Apple has not conveyed any plans to remove this page yet, but it is surely in their thoughts.
As a side thought, Apple could add an online version of the Mac App Store that is fully browsable – as opposed to the current one which only lets you look at certain apps. This would enable developers to receive more traffic from users of all platforms and advertise the Mac’s vast array of applications available to the user. This is only an idea, but could easily be turned into reality in the future.