[Neil Jones]

I wonder if Jeopardy! became a fixture in this country, and we had an enormous winning streak along the lines of Ken Jennings, would the producers want to carry on or would it be 100% all over again?

Almost certainly 100% again I would hae thought, I would be very surprised if there isn't a clause in the rules of contestant participation that producers can change the rules for any reason at any time and if that means you get kicked off after 75 shows, then it sucks to be you basically. Otherwise in theory you could stay on a show for the rest of your life.

I think it was Cash Trapped that took this to its logical conclusion, where you couldn't leave the show until whatever the scenario occurred that allowed you to leave legitimately (IIRC somebody ultimately decided sod this I'm off and walked).

[all new phil]

Quite enjoyed Jeopardy the few times I’ve caught it. It’s got quite a charming vibe to it - you can see why they went for Fry as host.

Only niggle I’ve got - the entire premise falls apart sometimes. Think it’s been mentioned already but you’d never answer some of the questions with the answers provided if they were the other way round. “What is 1984?” indeed…

[XIII]

I do like the show although I have noticed and this is due to me watching a lot of gameshows was that a fair numbers of the contestants have been other shows.

[tellyblues]

The odds on the same contestants appearing will be higher if producers want to cast people who are proven to be comfortable on TV and will probably have a good grasp of the game. Most "normal" people don't have the luxury of a life where they can just give up their responsibilities to appear on a gameshow so it's going to be those who do and contestants who make a living out of TV are in that category. There are also blacklists at production companies with regards to contestants so that narrows the list down even further.

[Flux]

There's also the fact that Jeopardy is a certain kind of show - in the same vein as Eggheads or University Challenge - where contestants need a certain level of academic knowledge to be competitive. The pool of possible contestants for formats which require more general/pop culture knowledge like Tipping Point, or next to no trivia like Catchphrase, is naturally going to be much larger.

[Neil Jones]

The odds on the same contestants appearing will be higher if producers want to cast people who are proven to be comfortable on TV and will probably have a good grasp of the game. Most "normal" people don't have the luxury of a life where they can just give up their responsibilities to appear on a gameshow so it's going to be those who do and contestants who make a living out of TV are in that category. There are also blacklists at production companies with regards to contestants so that narrows the list down even further.

Why would there be blacklists?
Aside from maybe winning too much money or having already appeared on a show, or being unsuitable for a certain show (or appearing somewhere and doing something inappropriate like exposing yourself) why else would you get blacklisted?

[JAS84]

You already listed some of the reasons, but here's what I think:

Anyone who's won too many shows before
Anyone with a criminal record
Anyone who's already been on the same show, unless they're a celebrity
Anyone who's a celebrity, unless it's a celebrity edition of the show
Anyone who is an employee of the production company or broadcaster, and their families
Anyone proven to have cheated when previously on a show

[Newshound47]

Did he depart after losing or is there a 5 wins maximum?

It's the payout which is going to hurt a recommission as much as the ratings - £30k over 5 episodes is a bit on the high side for the slot.

They could change it to £20/£40/£60/£80/£100 and £40/£80/£120/£160/£200 if they needed to reduce winnings.

[RhysJR]

You already listed some of the reasons, but here's what I think:

Anyone who's won too many shows before
Anyone with a criminal record
Anyone who's already been on the same show, unless they're a celebrity
Anyone who's a celebrity, unless it's a celebrity edition of the show
Anyone who is an employee of the production company or broadcaster, and their families
Anyone proven to have cheated when previously on a show

What's the definition/ cut off of celebrity in the case of a quiz/gameshows?

I think I've seen local Heart presenters on something like The Chase; they're obviously not A-listers, but are known by a section of the public and have a following.

[JAS84]

Uh, I'm pretty sure Heart presenters aren't local... that's a national radio network is it not?