When we transitioned to Windows Live Local we implemented new servers for the tiles for vector, ortho, and other imagery sources. This new setup is more scalable and better acommodates the kinds of traffic we need to handle for our own site and for our commercial customers and mashup builders. Until now, we have kept the old tile servers running to keep our v1 mashups running. But, alas, the time is approaching when we have to recover those servers and move on.
Commercial Control v1: We have updated the commercial control to reference the new tile sets. If you are referencing the commercial/v1 control on dev.virtualearth.net, your app is already updated and no changes are needed. Because we have not yet released a new version of the commercial control (it is coming) that implements the new look and feel, new imagery, etc., we will continue to support this version on the new tile servers. If you copied the commercial control locally (not recommended) and are not referencing the version on our dev... servers, then you must update your app by February 12th to reference our controls. (Yes, we know the documentation has out of date URLs; unfortunately we have a documentation backlog with tons of cool new products coming.)
Standard Control v1: There are no plans to update this version of the control, and applications must be upgraded to the Standard Control v2. The updates are minor and are outlined on a number of blog posts here. This applies whether you are referencing the control on our servers or have downloaded the control locally as it is the underlying images that are going away, not the control itself. If you have additional questions on how to update your app, see Via Virtual Earth, a great community site for VE dev--check out articles and utilize the forums. You can also contact me using the contact form on this site.
Standard Control v2: No changes needed as it is based on the new tile servers already.
I just want to reiterate that the best policy is to reference the controls on our servers. If you do, you will automatically recieve important bug fixes and avoid breaking changes like this one. We have updated the controls in place numerous times to fix bugs found by our customers in these beta versions and have had no impact for the overwhelming majority of applications, even with beta code. You will also benefit from updates to imagery as they are released by referencing the control.
PS - This also of course also affects applications that have directly hacked the VE tile servers. While this is not supported, we know you are out there and doing some pretty cool stuff for that matter. Unfortunately, you will have to dig through the code of the v2 control for the updated tile servers and scheme.