Our experience is that the Office add-ins won't work in Windows 7/ Office 2010.
Best approach is to add the SPP/ VTI amp module to Alfresco to get Sharepoint Protocol support.
CIFS is also fine in a lot of cases - edit directly or drag the file onto the __CheckInOut.exe file.
You'll need some fine tuning of authentication/ permissions in a larger environment but Alfresco does integrate with AD.
Regards,
Sasquatch