First, the good things:
1. The interface is super easy to navigate. Switching between screens isn't "blazing" fast, but the structure is easy enough that a even a relative technophobe could fumble his/her way through the channels and programs with minimal instruction.
2. Even while actively streaming, this thing doesn't pull more than a few watts. Great way to save some wear and tear on my XBox360, which is a heat-generating, noisy power-hog that is great for games but is a little overpowered and "underfeatured" when it comes to streaming tasks. The Roku draws minimal power, doesn't generate much heat, and is basically dead silent.
3. Loads, loads, loads of free content. Yes, the Roku will let you take advantage of your paid subscription services like Netflix, Amazon, HuluPlus, HBOGo, NHL Gamecenter, and the like, but where it really beats the life out of other streaming options (such as the XBox and Blu-Ray player I have previously used for streaming) is in the amount and variety of freely available content. Through various channels, users can access streams from CNN, BBC World News, and loads of other news streams from around the world. Like Mexican and South American soccer? No problem. Korean dramas? Japanese game shows? Classic movies? Newer movies? You can find all of it.
The not-so-great:
(1) When you first add a channel from the Roku website, it won't show up on the device right away. The slightly cumbersome workaround is just to pop into the settings menu and tell the unit to update the software. Once the unit confirms that the version of the operating software is up to date, it automatically downloads the new channels onto the device. Jump back to your channel menu and you're good to go. Really just a minor nuisance though.
Ultimately, I have to give this five stars for its ease of use, efficiency, for the wide variety of audio, video, and information content that is available (with much/most of it being completely free), and for the price point. I can't speak to the higher end variants of the Roku, but the LT is a big bang-for-the-buck gadget.