I know I'm new here, but here are my thoughts. The Vera "app store" built into the hub is really convenient. I don't have my Hubitat yet, but I know that on the Vera it's a PITA to manually load a plugin (usually at least 4 files, and then manually creating a parent device). The "store" based thing they have makes it easy.
I see people here are arguing that it's better that they maintain their own repos because they do this as a hobby. That's great, and that's what I do. However, when I'm done with my code, I submit it Vera's repo so it's all packaged up and available through their app store. You could do the same thing here, where devs only upload release code to make it easily available to users via a 1-click install inside the Hubitat UI.
Edit: Another thing to mention here is that Vera does a validation process on your code when you submit it. It generally takes them at least a few days. But, I'm sure it's to look it over and make sure people are doing anything malicious in it, and possibly installing it to make sure it doesn't crash LUUP. Having an official place to get apps from, that are vetted, is eventually going to be a requirement for widespread adoption of the platform. Casual users don't even know what github is. And people installing plugins from unknown sources and having problems is going to reflect badly (from the casual user perspective) on Hubitat itself, not the app developer.