I'm considering buying TV shows through iTunes. Normally I get my TV shows through a combination of DVD/Blu-ray, downloading and streaming online. However, I have an iPad now that can deal with high definition video better than my computer can, so I'm strongly considering taking that route.
Let's start with the three shows that I am actively watching.
Mawaru Penguindrum -- no official North American distribution.
My Little Pony: Frienship is Magic -- not available through iTunes, but each episode is uploaded to YouTube by the end of the day it initially airs.
Lost Girl -- streamed for free on Showcase's web site, available through iTunes (season pass for season 2: $34.99 HD/$30.99 SD).
Next let's look at some of the shows that I have recently bought on Blu-ray or DVD:
Doctor Who, Series 6, Part I (episodes 1-7): Cost of the Blu-ray box-set (1080p): $30.98 (let's say that I bought it for the current Amazon price of $25.99 though). Cost on iTunes (720p): $23.99.
Law & Order: Not really fair, as I just go the complete series DVD boxset, which ended up coming out to about $25 per season. Still, season 20 of L&O on iTunes (standard definition) goes for $34.99.
The Twilight Zone: Only the first three seasons (of five) are available on iTunes ($59.99 for season 1 in 720p HD). The Blu-ray (1080p) was close to $80 per season, which is closer to what season 2 goes for in iTunes ( $2.49 per episode for 37 episodes).
And now shows that I would consider buying through iTunes:
The Good Wife: I've only heard good things about this one. Season 1 on DVD (which I can never find in stores) goes for $44.99 normally, $30.14 currently on Amazon. On iTunes season 1 goes for $64.99 (HD) or $49.99 (SD). Subsequent seasons (the show is currently in its third season) are similarly priced (and a season pass is available for s3). Season 2 DVDs go for $59.99 normally, $44.99 currently on Amazon.
Doctor Who (classic series): These are a bargain in iTunes. Four-episode serials go for $5.99, six-episode serials for $8.99. The selection isn't great, but the price is good. (Compare with the DVDs of these serials -- The Talons of Weng-Chiang, an eight-episode serial, with extras goes for $43.98 normally on DVD, currently $34.99 on Amazon.)
I like the idea of the season pass, getting a new episode just after it airs. With some shows I like to keep up with the current episodes (like Doctor Who, Lost Girl and A Game of Thrones), whereas others I can wait until the season is long over.
One of the choices that I have made is that the shows that I do buy through iTunes, I will not buy again on disc. Buying discs of the shows that I follow has been something that I have done, but I think buying the show once is good enough (though that rule seemingly hasn't applied to anime DVDs).
Another thing that I have noticed with this new way to buy my shows is that I am not in a rush to buy the shows on iTunes. With disc releases, I usually buy them within a week of release (whether I'm going to watch them immediately or not). I haven't started collecting TV episodes in iTunes yet (the one show that I have bought, a classic Doctor Who serial, I have watched most of since buying).