[acefire]

With WP 8, a new feature would be the support for mSD cards.

Another new feature would be the ability to install apps FROM the SD card itself. What does this mean? It means that you can simply copy the XAP file and place it in the SD card of your WP device, and you will be able to install it from there. (This has even been put into place for some marketplace apps which do not offer downloads through the marketplace although they are official apps)

It's easy to download apps and games from the Windows Phone Store and install them on your phone, but you can also transfer, or sideload, them from an SD card to your phone (if your phone supports an SD card).

To sideload an app or game, you'll need to have an SD card that contains one or more Windows Phone app files, also known as .XAP files. You can download .XAP files to your PC, and then move the files to the phone's SD card.

To download .XAP files from the Windows Phone Store on the web
Open a web browser and go to www.windowsphone.com.

Click Apps + Games, and then click the app you want to download.

Scroll down on the webpage, and then click Download and install manually (below the app requirements and supported languages).

When prompted, save the .XAP file to a location on your computer, SD card, or storage device.

Note
If you download the .XAP file to a location other than an SD card supported by your phone, you'll need to move or copy the file to an SD card to install it on your phone.

To install apps and games from your phone's SD card

Insert an SD card that contains one or more .XAP files into your phone.

On Start , tap Store , and then tap SD card.

Note
If you've just inserted the SD card or added the .XAP files, you might need to wait a few minutes before you can access your SD card from the Store.

Select the apps you want, and then tap Install.

Notes
Apps that can be installed are listed under Compatible apps.
You'll need to have the latest version of the .XAP file from the Store on your SD card before you can install it. If it isn't the latest version, it'll be listed under Incompatible apps.
Installed apps appear in the App list and games appear in the Games Hub. Depending on the specific app or game, you'll be able to use them as follows:

Free apps and games can be used immediately.
Paid apps and games that have a trial will be available as a trial version that you can purchase later.
Paid apps and games without a trial must be purchased before you can use them.

What is yet to be seen is whether cracked XAPs will be able to be installed via this method. If they are allowed to be installed, our WP 8 devices no longer have to be dev-unlocked in order to install custom XAPs.

If they are blocked, I'm pretty certain someone will find a way to bypass security checks.

Isn't this good news?

I wonder how this will be handled by devices that don't have SD card slots, like my HTC 8X from Verizon...

If I plug in my phone via USB I get a list of folders, I wonder if we could add a apps folder or something so it will see the XAPs...

I'm sure there will be way of changing part of the files, like change the name but, all XAPs from the marketplace are encrypted, so accessing the files to make changes might be hard.

Also this might be fine for WP7/7.8 apps but, what about WP8 ? There is currently No unlocks for Wp8 besides a dev account and even that for me gets me only 3 apps.

At this point unless you have a dev account for a WP8 device, it's game over if you want to hack anything but, time will tell, I am sure the best of the best are already working on it...