If you want to shoot video, get a "semi-pro" camera such as the Sony EX and PD series.
Forget the PDs. Nobody shoots standard def any more. I've been using EX1 & EX3 cameras for the past few years, but to be quite honest, for what they cost, you're MUCH better off getting a Panasonic AF101 and an external recorder like the Ninja box so you can record straight to 10-Bit 4:2:2 ProRes, and still have a couple of grand left over for some really nice Nikon glass.
There's a reason these are used for low-budget TV production and not DSLR's - put simply, they work! Can be given to a runner with 2 days training and produce footage that is (...occasionally...) of broadcast standard!
When you say "of broadcast standard" you're talking about the camera op's ability? and not the actual file format being output? The EX1 & EX3 are only barely within broadcast technical specs, and are only allowed to be used for a small percentage of a total program's footage (according to the BBC anyway).
The thing is, a 5DMk2 + rig + a couple of lenses is going to cost you less than an EX3 anyway, and you can do far more with it. And it's generally a case of "were" more than "are" these days.
The only purpose for using a DSLR is if you need an ultra-shallow DoF - but its far from cheap once you get the necessary monitoring and follow-focus gear, and you'll end up with 3-4 people around the camera just to make a decent shot...so might as well have got some proper gear in the first place...
You need all the same gear and people regardless of whether you're using an EX1/EX3 with a 35mm adapter, an HDSLR, or an Arri Alexa, but the DSLR is still probably going to end up the cheapest.
you also won't have overheating sensor or battery issues
Overheating is camera-specific. I've never seen a Nikon overheat, and Canon seem to have solved the problem in the 60D & 600D, so I'm sure the problem will also be solved in the 7D & 5DMk2 replacements when they're finally announced.
As for the one episode of House - and I'll say that again, the ONE episode of House - shot on 5D's whilst carefully avoiding any difficult shots... was partly marketting gimmic, partly technology demonstration, and partly to fit into very small spaces with a ultra-shallow DoF. All the shots could all have been achieved with conventional film gear, of course - but would they have got any publicity if they said "we shot the season finale entirely on SS16..."? nope...
As for the
twenty four episodes in Season 7 of house - and I'll say that again, the
TWENTY FOUR episodes in Season 7 of house - that are being shot on a mix of Arri Alexa, 5DMk2 and other cameras, they use them because there are times when it's practical to do so (and much less costly).
The season finale was nothing to do with getting ultra shallow DOF. He used f/1.2 for only one scene in the entire episode. It was the fact that the cameras themselves were physically small, and it cut the production time well under half because they didn't have to take sets apart to cover multiple camera angles with more traditionally sized video cameras. The fact that the entire episode was shot with them, sure I'll give you that one, it was just to prove it could be done, but there were very practical reasons as to why they were used for the majority of the shots where you're filming in a set that only has a ceiling of 18-24" high.
Gale Tattersall's done plenty of interviews online, I helped out with the one at Planet5D, and he's answered all these questions a million times as to why they were used, and why they will continue to use them.
Stargate Studios also used HDSLRs for many of the driving plates in the final season too. HDSLRs aren't a one trick pony, they can do far much more than just shallow depth of field. Go stick a 24mm lens on your DSLR @ f/11 and tell me how shallow it is.
They're a tool, like any other camera. There's a right time and place to use them and a wrong one.
A bit of practice gettign used to holding the camera steady and perfocusing etc, seems to go ok.
