Mike wants to "cut the cord" because he just found out that Aereo is available to him. Leo says that's all he needs, as Aereo offers high quality HD broadcast quality thanks to millions of tiny antennas. It offers DVR capability as well.
Aereo is only half the equation, though. Mike can also get most of the cable programming streaming via Netflix, Amazon Prime and Hulu. To watch Aereo on the Roku, he'll need a Roku, but he would want to get one for Netflix anyway.
On the Roku, are there fees for the channels? Leo says some have a subscription fee, like Netflix and Hulu, but there's free and hidden channels as well. Check out Roku-Channels.com. Another option is an Apple TV, but only if he's in the iTunes ecosystem.