Is there any chance you guys could develop a Skritter application for the Windows Phone? My iTouch is out-dated (2 generation) and won't download the Skritter app cuz my iPod won't download iOS 5 apps :(

Omg yes please

As much as everyone would like to have an Android, Windows Phone, Windows 8 and other apps, you have to keep in mind that the iOS app was mainly developed by a single person, with a second person who learned Objective C just for the purpose of being able to help out with the iOS app. It took thousands of hours to develop the Skritter iOS app. It will take thousands more to continue to develop and support it. The further development of the web site already had to take a back seat to the iOS app in the past few years and now that it is here, the Skritter team's attention will remain split between the two. Nobody can reasonably expect them to manage anything more than that at this point.
Even if they did have the resources to pull it off, Android would be the next one in line, as their marketing share (only counting Android 4.x) is currently almost five times as much as that of Windows Phone. Microsoft also has the annoying tendency to completely change their APIs with every release and even Windows Phone 8 will only be guaranteed for 18 months in that regard. But at least they made it possible to fully develop applications in C++ this time around. Android also supports this, but only in part. Apple continues to stick to Objective-C because they have a vested interest in keeping things closed. Perhaps, one day, everyone will get a clue and it will be possible to develop any application fully in C++, with just a limited amount of platform specific code required to make it work across the various mobile and desktop platforms of this world.

We don't have any plans to make a Windows Phone app, no. As 范博涵 said, it's a ton of work to do a native client, and it doesn't seem worth it for the Windows Phone market.