I remember the first time I ever saw an episode of Total Drama Island. It was Dodgebrawl, and I instantly fell in love with the concept of a cartoon reality show. From then on, I followed it, and even though I was sad was LeShawna, my favorite, was eliminated, it still wasn't a disappointing conclusion.
Total Drama Action was OK. I liked seeing Justin and Beth return, but I missed Katie and Sadie...anyway, it got a little gimmicky when they added Owen back in to be a mole. At least Beth won in Canada...
Now I see Total Drama World Tour, and it doesn't appease me. They got rid of some of the best characters (Izzy, LeShawna, Lindsay, DJ, Duncan) way too early, while [SPOILER] they're keeping Alejandro, Sierra, and CODY until the F4. (I'm glad that Heather makes it and Blaineley gets a chance though. :D)[/SPOILER]
Now, looking at the Wikipedia page for the fourth season, Total Drama Reloaded, the cast looks ABYSMAL. It doesn't appear possible to recreate the feelings we experienced with the first cast: The ghetto-charm of LeShawna, the ditziness of Lindsay, and the love-hate relationship of Heather.
In my opinion, they should continue with the original 22. Some characters (Eva, Katie, Sadie) have not even had a second chance. But no, we're going to be bombarded with girls whose names all end in an "EE" sound and a boy named "Lightning." sigh.