Give this a whirl.. http://www.googletvforum.org/forum/google-tv-faqs/162-sync-pc-ext-hd-logitech-revue.html
The HD itself is connected to the Revue, not a PC that I can stream the media from. I only have laptops in my house, so I was hoping to be able to connect to the HD through the Revue...
So, you believe that a s/w update would most likely be the ticket, rather than hardware?? That's the way I'm seeing it at...
I don't see any reason that it would take different HW, more likely it will take an application from the market. This application, Estrongs File Manager allows you to explore Android Phone contents over the lan already, so likely it would allow you to do the same once the APP market is available for the GTV platform.
Since you have laptops then another option is to get a NAS device that supports DLNA...then both the laptops and Google TV can access the drive at the same time. Another option is to get a Router like the Cisco/Linksys E3000 or E4200 that has a built in USB port and UPnP AV sharing and plug in a hard drive to the USB port of these routers.