Former SoftGrid is now Microsoft Application Virtualization (App-V). It is similar to other solutions offered by other providers, like (now) VMWare’s ThinApp or Citrix. Apparently, it will be possible to access an application remotely, similar to Citrix. It will also be possible to create portable applications that do not have to be installed, similar to ThinApp.
Microsoft Application Virtualization 4.5 will be available as part of the Microsoft Desktop Optimization Pack and Microsoft Application Virtualization for Terminal Services
What I would ultimately like to see in the application virtualization space is a solution that works in a manner similar to SandBoxie. The whole installation can be boxed and, once done, packaged in a portable version. This is what ThinApp does but I do not like having a separate, clean machine just for creating portable applications.