It is important to note that the listed channels on the Roku box are not your only options. There are a lot of "private" channels (like the one I linked to) that allow you to bring content to your TV through the Roku. For example, you could send YouTube to the Roku through private channels.
I haven't had too much time to fuss around with the nuts and bolts but I am told that with a little time investment, you can pretty much get anything that is available on basic cable over the Internet instead, allowing you to truly cut the cord with your cable company (though you will still need an internet connection). The only reason I haven't cut my basic cable yet is because I also bundle my phone and internet through Verizon and cutting the basic cable will only make those services go up.
I’ve been digging around the public and private stuff, but haven’t come up with that much of interest. However, it appears (to me at least) that they’re not showing all their content.
I’ll look into it further. Thanks for the information.