The Windows Phone Developer Center has a great distribution channel. I haven't heard much mention of it elsewhere, so I thought I would make a quick post to share some info about it.
Android lets you do whatever you want, and install apps from anyone, from anywhere. Apple allows you to distribute your app to up to 100 devices, as long as they are all part of the provisioned device list, which means you need to be aware of all devices before you build. Microsoft has taken a middle of the road approach.
Microsoft's approach allows you to specify a list of users's email addresses, and those users will see your app in the App store just as if it was public. Just today I noticed that the beta distribution channel supports up to 10,000 users, ( I believe it was only 100 last time I looked. ) This could allow for some very vast betas! Another benefit of this approach is that you can actually test your marketplace presence. You can actually see what your app will look like in the store, and decide if you need more screen-shots, better screen-shots, more description, and so on. Although it may be a hassle to manage 10,000 email addresses in the web page's input box, I still think this is a great approach to beta distribution in that there is no need to rebuild or re-upload, and users can be added and removed ad-hoc. Is anyone using this approach to test their apps with a large scale beta groups? Would you like to invite me to try your app? ( purplecabbage[at]hotmail.com )