All My Mac Apps is a fluid app that lets you browse the AllMyMacApps.net. Fluid essentially lets you access any website from an application on your Mac. So, basically, All My Mac Apps on your Mac is the same as browsing the website on your web browser.
The first time I run the app, I had to resize it a bit to see the full website. All My Mac Apps is a website that lets you discover new applications and download them easily. All the apps are displayed on a virtual shelf. There are 20 per page, and you can filter them by free, paid or both, or choose a category. Some of the available categories are 3D, Audio, Backup, Browser, Business, etc. If you move your mouse over an app icon, you will see a little menu that lets you add an app to your app box, download it, report a broken link or see a window with additional information about the application.
I tried downloading apps using the Fluid version of All My Mac Apps, but nothing happened when I clicked on the download button. I could add apps to the app box without problems.
In short, this is a nice app if you want to browse All My Mac Apps from your desktop, but it seems to have limited functionality.