as has been said, you won't be getting channels in the traditional sense, but you will be getting shows. And how you get each show will depend on that show.
you need to look at how you watch tv, and make a decision based on that.
iTunes has a lot of shows available next day (the day after they air), but you'll pay $54 dollars for a HD season, (22 episodes or about 6-7 months of tv). it's worth it if you're only into a few shows. if your cable bill is $54 a month, then more than 12 shows, and you've cost yourself more.
Check out the shows you watch though. While Dexter is available, it's a whole season behind.
Hulu, also has a lot of shows available next day, but again it's limited to certain shows.
local television channels - if you have a cable modem, they will be available on the cable coming into your house, most of the time in HD. Or you can get an antenna.
check out the
silicone dust site to see what you can expect to find.
You'll need a HD tuner, most of the time built into the TV, or if you want DVR functionality, then something like
EyeTV and an external tuner of some kind.
for tuners, i've got the
HDHomerun it's dual tuner, but only gets unencrypted channels off the cable, so for me, it's the locals in HD and TBS in SD. I use
mythtv a linux based DVR software instead of the EyeTV.
there is also the
HDHomerun Prime it's a triple tuner, and with a cablecard, you can get the encrypted channels, but... you'll still be paying for cable TV service.
These are nice, since the tuner and software connect over ethernet, i can place the tuner by where the cable comes in, and not by the computer running the software.
also, for any HD recording, you'll need a ton of storage, a 1 hour show is typically about 5GB.
Sports - if you're into sports, you'll only get what you have access to on local broadcasts, although there are options for MLB, NHL, and NBA on appleTV, and similar options for certain sports to watch in a web browser, if you went with a mini connected to the TV.
for things like ESPN, you're kinda out of luck.
The other big thing to keep in mind is the
WAF
You need to remember all people in the house when making these decisions.
and to keep it simple, having too many remotes, or a wireless mouse and keyboard on the couch might not
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there is also the option of downloading from other sources, pretty much every show is available shortly after airing, from (probably not that legal) places online. but that's a risk you'll have to look at and decide it you're willing to take, I've had friends receive cut off notices from their ISPs for downloading shows.
And you'll also need to keep in mind how you'll be able to play these files once you have them, most should be directly playable on a mini, but would have to be converted to play on AppleTV.
