Have they changed or have not, depends largely on how much you have played those games.
For example in Pokemon, battling with 2 pokemons was a major change in strategic point of wiev. But i guess for non-pokemon gamer the change was pretty much nothing.
Also, there was pretty big change in the Twilight Princess gameplay (for the bad, i think), but it's definately something that anyone, who's not a fan of the series, will notice.
Edit: I was meaning "will not notice".
About Zelda, Phantom Hourglass has big change on gameplay. And Pokemon Stadiums & Colosseum were pretty much different from previous pokemons. But you can count them out, since these are either new ones or exceptions, and point in this thread was that some active series change slowly (or not at all).
Ei Kiinasti.
Eikä Japanisti.
Vaan pannaan jalalla koreasti.
Nintendo games sell only on Nintendo system.
