Change Your MapControl.js (to V2)

Virtual Earth now hosts it's MapControl at a different location. In order to take advantage of this, point your javascript link to https://dev.virtualearth.net/standard/v2/MapControl.js or download it into your project (much easier for if and when it's changed in the future).

Here's the full scoop on the Virtual Earth "official" blog:

Virtual Earth Control URLs Changing
To provide a stable and predictable set of tools for our developers through the future, we are moving the all controls for Virtual Earth to a new location. The original control locations will be retired in the coming weeks to prepare for changes required by the Windows Live Local announcement.  Updating your applications now will prevent these changes from impacting your applications and ensure future changes have minimal impact as well.

The Standard Control, previously available at https://virtualearth.msn.com/js/MapControl.js, will be moved to a new home here:
https://dev.virtualearth.net/standard/v2/MapControl.js

The current version of the Commercial Control is also being migrated to the new location.  The new location of the files referenced in the Commercial Control SDK (which will be updated shortly to reflect the changing URLs) are now: 
https://dev.virtualearth.net/standard/v2/MapControl.css
https://dev.virtualearth.net/standard/v2/MapControl.js

If your application references the old URLs, it is important that you update it as soon as you can to avoid changes to the Virtual Earth URL related to the Windows Live Local announcement from affecting your application.  The controls hosted at the new location are the same controls you are currently using, just hosted elsewhere—no other changes should be needed to your code base. 

If you have downloaded the control and are hosting it locally (not recommended), you must update your application to reference the new location as a static script reference in your application or it will also break when the old URL is retired.

We apologize for any inconvenience this causes; however, it is a necessary step in providing a stable, predictable developer platform moving forward.   As is true for many beta products, especially those built for developers, Virtual Earth is going through these changes to provide a more stable infrastructure than our earlier preview code provided.  As always, we will strive to minimize breaking changes, provide sufficient notification of those changes, and generally provide a good experience for our developers.  We thank you for your commitment to the Virtual Earth development platform, and look forward to sharing all the advances we are making with you and your customers.