From what I can tell, typically, for movies, the chronological release order is something like:

Cinemas » DVD » BD » aired on free-to-air (FTA) TV

Seems to make sense to me - people who want to see it first pay to do so, and the people who really want to see it forgo having their own copy of the movie.  After that, it's aired on FTA TV for everyone else.

For TV series:
aired on FTA TV » DVD/BD

I guess it makes sense to air a "TV series" on TV first, but ignoring this naming convention, it's interesting to note that it seems to be a bit of a reversal of the process for movies.

Discuss.

I'd say both are pretty much a once off thing.  TV series are longer so have more ability to generate revenue from commercials than movies.  But on the other hand, they _are_ longer, so *may* take more effort to produce.
I don't know about the figures, but if they released series' on DVD first, would that be more or less profitable than airing it first?

Compare the most expensive films with the most expensive television series.

Big budget movies from Hollywood get hundreds of millions put into it. I think the most expensive thus far was Pirates of the Caribbean 3 which was like $300million USD. They really need to recoup that serious amount of money and also make profit. Having the film in cinemas and charging $10 to $20 (depending on type ticket) is a very viable way for them to generate their investment back.

TV series don't screen at cinemas for reasons that there's too many episodes. People aren't going to pay for a ticket for every episode. Also consider that each episode is far far cheaper to produce than a big budget film and that each episode is pumped out much quicker. The storylines are generally drawn out more (because they have more time) and this makes writing a bit easier. TV series budgets can vary a lot, but will generally be a few million per episode. Recently, Boardwalk Empire is probably the most expensive series with reports that the pilot cost $50million (other reports say $18million). Either way, it is still a lot of money in TV-land.

A TV show makes its money back in advertising, as previously stated. A big budgeted show will generally be expected to have a large viewership. In turn, networks are able to demand a lot of cash for adspace during the show. It would be less profitable to release the show on DVD first because they completely lose the advertising possibilities. The money they have to make back would need to come from DVD sales alone. Also, it would be difficult to sell a new TV show that noone has seen before on DVD.

Interesting thoughts you've brought up Zinga. And yeah, it's interesting how it's reversed for either medium.