I think we'll begin to see a ton of improvements to both App Stores once the Mac App Store is open for submissions, namely: bundles (see iLife), more/unlimited

I think we'll begin to see a ton of improvements to both App Stores once the Mac App Store is open for submissions, namely: bundles (see iLife), more/unlimited promo codes (for transitioning users from non-App Store to App Store), and customizable "developer" pages (rather than just a list of apps).