Only certain "apps". For instance, the Lion update is an image with an installer that mounts then runs. (See the Lion thread for information) Basically as I explained, when you run the installer inside the ISO/DMG, it creates a bootable partition on the target drive that contains a simple installer and everything that is needed to boot, then reboots onto it to complete the install. It's quite amazing and genius and shows exactly how the OS X upgrade future is going to be. (Providing I can A: backup this disk image for future installing and B: can mount and install on a different Mac in the future, I don't care if they go completely disc-less this time.)mrkgoo said:Ah, so you can download dmgs from the AppStore? Cool.
And Xcode would make sense too since it is a big thing and not just an application. So it'll probably download an image then install from it. Don't quote me on it though, but seeing as Xcode is a whole shitload of apps and utilities and not just a single self-contained app, it basically requires a full installer. This is probably how bigger apps like PhotoShop and Office would work if they ever made it to the App Store. The store would download an image, mount it then run a script to copy the files to the right place or run the installer if it requires finer tuning.