The stick effectively adds Google TV functionality to Sony's line of Bravia televisions, and that's it. You won't be able to hook it up to every MHL or HDMI-touting television on the market - just Sony's 2013 line of televisions. It doesn't create an overlay on top of the existing Bravia software, either, but instead integrates "seamlessly with Sony’s own BRAVIA apps and navigation to deliver an amazing connected TV viewing experience.”
The Smart Stick offers YouTube, app access through Google Play, including Amazon Video and Vudu in the US, Google search for results from cable/satellite providers, and it links to a home network wirelessly, as you've come to expect with Google TV.
As for hardware specifics, the Smart Stick packs 8GB of on-board storage, an MHL port for connection, an optional HDMI port, and a USB port for power. Like the Chromecast, you aren't able to just go the MHL route - you'll also need to connect with USB to keep the Smart Stick running. The remote is larger than the Smart Stick itself, which even features a microphone to search content, apps, and the web.
It doesn't really do the same kind of thing as Chromecast, being more of an Apple TV or Roku box competitor and considerably more expensive, but its form factor could appeal to many who would prefer to hide their kit away. The Smart Stick is available now at Sony Stores and retailers in the US for $149.
