Ever-expanding DK crew? There hasn't been a new Kong since 1999. (Not that I'm complaining. In my opinion, the only ones the series really "needs" are Donkey, Diddy, Dixie, and Cranky, excluding prominent non-Kong characters, and as of Tropical Freeze they're all back in the spotlight.)
Donkey Kong fans have a history of being bitter because, from 1996-2010, you couldn't get a Donkey Kong game that actually played (and "felt," I guess) like a Donkey Kong game. We had Donkey Kong 64, which is popular among general Nintendo fans but polarizing among DK fans; we had gimmicky, B-tier spin-offs like Mario Vs. Donkey Kong, Donkey Konga, King of Swing, Barrel Blast / Jet Race, and Jungle Climber; and we had Jungle Beat, which has good gameplay but tried to wipe 99% of the series' characters, settings, and continuity (which DK does have).
That's like if Nintendo suddenly decided that Luigi, Peach, and Bowser are old hat, openly badmouthed the popular Mario games, and released SMB2/USA as the next major game in the series, with Mario himself as the only returning character. People would cry foul. You know how Metroid fans are upset because the only thing they've gotten since Metroid Prime 3 is an uninterrupted stream of weird crap they don't want? That's how the DK fandom felt for fourteen solid years. Can you blame us for being a little picky?
Luckily, Donkey Kong Country Returns and Tropical Freeze are both fantastic, especially the latter. They really feel like modern continuations of Rare's 2D Donkey Kong games. The partner system and some key mechanics (like rolling) have been radically tweaked, but everything that, in my opinion, is truly important to the series - the familiar characters; the naturalistic setting; the moody, atmospheric music; the emphasis on exploration and attention to detail - is right as it should be. They even introduced some great new characters that feel right at home in the Donkey Kong Country world, unlike anything from Jungle Beat.
...Jesus, that ran a lot longer than I planned. But there you go. That's why we folk over at DK Vine were a little miffed at the Metroid fandom for a while, too. We kept hearing that Retro Studios was too good for Donkey Kong and that Tropical Freeze was a "waste of talent." God knows, our series doesn't deserve a competent developer that actually likes and understands it.