Simple proposal.. How about a zipping an application and merely naming it .appz (or just plain zip)
The only reason why Mac application can't be distributed like Windows .exe files is that Mac applications are actually directories. Excluding .pkg installers 99.99% of the time the .dmg file is merely just a container for the single .app directory.
Safari automatically unpacks .zip files by default on download. Where's the mystery here. Why bother with dmg in the first place
The main reason they haven't done it on OS X is that it would be completely backwards-incompatible. They should have done it in Snow Leopard (an easy choice if your app uses GC), but if they did they didn't tell anyone. Instead they added optional zip/deflate compression to HFS, and used it for most of the system files.
The only reason why Mac application can't be distributed like Windows .exe files is that Mac applications are actually directories. Excluding .pkg installers 99.99% of the time the .dmg file is merely just a container for the single .app directory.
Safari automatically unpacks .zip files by default on download. Where's the mystery here. Why bother with dmg in the first place