Typical disclaimer here: Your mileage may vary. Feel free to disagree, but please act civilized.
I've limited it to actual games, so stuff like Anything to Win won't be making it. Also, if it's not on BEFORE August 1, 2006, it's not here. Sorry, Chain Reaction and StarFace.
Honorable Mention: Celebrity Blackjack
It's why CPS is good TV, too, although Caroline Rhea was probably too much for my tastes.
10: I've Got a Secret
The key to how good this show is depends on your opinion of the original. If you liked it, you'll like this. If not, you won't. Plain and simple. Nothing's really changed except the faces.
9: Poker Royale series
I liked it because of its fairly innovative formats and ability to attract some names. Sure, there were some not-so-good series, but the complete body of work was sound.
8: BallBreakers
If Sal Masakela didn't get credibility with the non X-gamers, then he's the most underrated host on Earth. He was tight, Ewa was...Ewa, the game was surprisingly fun, and the production values were pretty good. The only thing they didn't need was Adrienne, but you can't win em all. If you watched "Texas Hold Em Billiards" the other day, then you may have appreciated this show a little more.
7: Cram
Yeah, it was a little kitschy, but that was the point. It had enough kitsch to be amusing, but had enough game to be not annoying. It wasn't as tortuous as, say, The Chamber, but now that I've been awake longer than I should have, I feel new appreciation for it.
6: Hollywood Showdown
Quite possibly, the first credible original GSN ever had. It made Jackpot more credible than it ever needed to be and introduced us to a Mr. Todd Newton. There's a reason TV Guide Channel is keeping it alive, and it's because it's pretty damn good.
5: World Series of Blackjack
I may be overrating this because I have to write about it, but it has a place on this countdown. I feel it's improving every season and this one has enough added goodness to make it good to watch. It's certainly had moments and great finishes. It's worth watching.
4: Whammy! The All-New Press Your Luck
You can destroy a lot of things, but you can't devalue the Random Element. GSM proved it and so did Whammy. It also didn't hurt that everything else wasn't so bad, either. Sure, the budget wasn't that spectacular, but you still had people winning $10,000 regularly, and that's not bad. Sure, it wasn't the old Press Your Luck, but it didn't want to be and it didn't have to be. It was plenty enjoyable and some of the board innovations made it even better.
3: Russian Roulette
Yes, the dangling of a $100,000 carrot helped, but it was still a great game. It had all the emotions: excitement, drama, tension, anger between players, and comedy. This game probably would've freaked me out as a kid, but since I knew better, I realized it was freaking awesome.
2: High Stakes Poker
A common myth in game shows is that celebrities add cred to dying series. A common truth in poker shows is that Doyle Brunson adds cred to an oversaturated genre. Long story short: if Doyle's in it, it has to be good. High Stakes Poker's greatest quality is in its simplicity: players play poker just like you would at home, only the stakes are.....unsurprisingly....high. If you like poker on TV, the only reason you shouldn't be watching this is that you don't have GSN and stealing cable is a crime. Otherwise, watch darn it.
And if you've been following along, you probably know what's coming next--both name AND number.
#1: Lingo
It's the little engine that could churn out over 250 episodes. No other GSN original comes close. Hell, they could've sold the reruns to some other game show channel and it would still probably turn out ratings. Some people have been critical of the game's overnecessity of luck, but there's enough intellect and skill to overwhelm luck when necessary. I honestly think it's not so much luck as it is inevitability, but that's a debate for another time. It's a highly addictive, highly play-at-home, a nice bit of intangibles thrown in, and now that the money has (sort of) gone up, it's even better. It's about a perfect a show that GSN will make and maybe the most perfect game show of the past 5 years period.
That's it. That's the list. I'm sure you disagree, so let's hear it.