Rick Walrond, the developer of the AlphaDrops, has uploaded a video to YouTube in which he demonstrates how he ported his game from Windows Phone to Windows 8. It's a good example of the synergies that Microsoft hopes to create by more closely aligning the two platforms. In this case 90% of the Silverlight code is common between the two versions of the game.

The video shows the game running on a Windows Phone powered Samsung Focus and a Windows 8 (Developer Preview Edition) powered Samsung Series 7 Slate. During the video Walrond notes that the port took from Windows Phone to Windows 8 about two weeks and demonstrates how the game's key functionality works on both devices and how the two versions share common high score tables. 

In a YouTube comment he notes:

I re-used upwards of 90% of my code. In fact the thing that took me the longest was figuring out how to adapt the game to the larger screen. To bring over a screen from WP7, I simply copied the .XAML and .CS file and then made a few code changes. There are some functions I had to change and there where a few things in the XAML that caused my W8 App to be unstable (Microsoft will no doubt fix this) but once I worked around them, it was smooth and easy.

Via The Verge and NeoWin