Attention: In this blog post I am discussing a configuration that is possible, but not officially supported by Microsoft at this point in time.  Feel free to use this – but understand that you are in an unsupported configuration.

Thanks to Ben Armstrong for this post

his blog here...

Alex

From Technet site....

As 64-bit computing becomes more commonplace in the enterprise, the MDOP team has announced that App-V 4.6 be the first version of App-V to support both x64 and x86 Windows platforms and the primary focus of the release is to enable App-V to take advantage of 64-bit Windows platforms including Windows 7 and Windows Server 2008 R2. You will also find improvements in the App-V Sequencer such as simplifying the workflow for creating virtual applications and adding the ability to sequence true 64-bit applications. If you are running Windows XP or Windows Vista, you can also use App-V 4.6 Beta and take advantage of the support for Office 2010 and 64-bit platform support.

You can try out App-V 4.6 by registering for and downloading the beta from Microsoft Connect.