Played through the first world and a half, and so far I'm really liking it. It's a lot of fun.
The controls take a bit to get used to, but they're really not that bad. I switched to Wiimote+Nunchuk, because it's kind of a pain on the wrists to have to shake while holding the wiimote sideways. Also, I really don't like the Wiimote's d-pad.
The only downside is that ground-pounding with the Wiimote+Nunchuk requires you shake both of the controllers alternatively, but it's hardly an issue. If you shake the Wiimote or Nunchuk by itself, you'll do a single pound, which is enough for the chests and stuff anyways.
The music is pretty awesome, despite it only being remixes of the DKC trilogy OSTs. The graphics are amazing. Normally, when games that look awesome in 2D transfer over to 3D, they tend to look cheesy and bland(For example, Sonic 4. Rocket Knight on XBLA/Steam/PSN had this issue to an extent as well) but this looks amazing. They did a fantastic job on the the audio and visuals.
It really annoys me to see how many people are knocking the game. Not on GBATemp, but other sites.
I've heard complaints from having a health bar, to no Kremlings, to stuff as minor as there not being an animated DK walking on the map screen. None of which are really that big of a deal. Instant-deaths still exist. I understand that people dislike the lack of the original enemies, but it's hardly worth complaining over. The last one... Ugh, not even gonna touch that one. Probably the only legitimate complaint I've heard was about the lack of water levels. I haven't personally played DKC1-3, but from what I've heard, they were kind of dull anyways. Still, I suppose it's somewhat legitimate.
Seriously, I wish people would chill out. The game is a lot of fun, and so far it seems to have a lot of replay value. The levels aren't terribly long so far, but I haven't actually 100%'d ANY of them yet. The puzzle pieces are pretty well hidden, and even some of the KONG emblems are tricky to get. For example, there's one in the rail cart level that's particularly annoying. So, it seems there's quite a bit to go back and find.
The level design so far is really good. There hasn't been a dull level so far. The first boss fight was really neat, despite being pretty easy. I loved the reactions from the "crowd" and the fight would've offered a small bit of challenge, had the boss not popped out a heart after every hit.