Great news for people working on Virtual Machines with BizTalk 2013 on Microsoft Azure.
BizTalk Server 2013 Development Edition is now available as a pre-built image you can select inside the Image Gallery.
I believe this image is only available to uses how have Azure through MSDN. I tried to access it through another Azure account I had and was not able to see the image.
I will be testing out the Image over the weekend to see how it looks.
Enjoy.