Slingbox's latest Watch software update includes a new feature that allows owners to invite Facebook friends to "sling in" and watch their video stream. The update specifically applies to the newer Slingbox 350 and Slingbox 500 models.

Engadget points out that only one connection is allowed at a time, meaning a Facebook friend could watch but only when you aren't using the stream from the "master" account. And as the owner of the account, you have the ability to interrupt a friend's viewing but they can't interrupt you.

Other new features include improved zoom control to handle more aspect ratios. Now, you can choose between default, anamorphic, letter box, pillar box and window box without issue. Additionally, the pause button has been moved next to the Time Shift buffer control on the video screen. Note, however, that the Time Shift buffer is only available on Windows computers.

Slingbox has also improved device search setup. This means that Watch will now be more likely to find your A/V device's manufacturer and model during setup or when you reconfigure an input on your Slingbox.

If you're on a Windows PC running Vista or newer, you should be good to go so long as you're running a somewhat updated version of Internet Explorer, Firefox or Chrome.  It's worth pointing out that Windows 8 is only supported in Desktop Mode. For Mac, you'll need Snow Leopard or higher and an updated version of Safari, Firefox or Chrome to get started.