Ash Paulsen of GameXplain did a review for the game, and while he loved the game at it's core (with some minor criticisms about bosses and the implementations of some aspects like the mini-quizzes, minecart rides, and mini-games), the massive number of framerate drops made the game really difficult to play, and thus recommended the game only to people who will absolutely LOVE this game and can deal with that kind of thing (the fact that he emphasized it throughout the review when he usually doesn't bother talking about graphics and framerates until the end indicates how bad he felt it was).
Ash then made a follow-up video, showing the game after it's initial patch and giving his impressions on the new and improved version of Yooka-Laylee:https://www.youtube.com/watch?v=T1LNDsl3HJE
Aside from areas where there are a lot of particles or there's a lot on-screen (like the flame pillars in the first world), everything else has been significantly improved, at least as far as he can tell. There ARE random framerate drops here and there, and the game's still at 30 fps instead of the 60 fps the PC version has, but otherwise it's a much smoother experience.
So that's good news for me! That was what I was most concerned about with this game, so it's great to hear that's been mostly fixed! I DO hope Playtonic continues to listen to criticism like this, about odd graphical glitches and framerate drops so that they can constantly improve and polish the game to a mirror shine! After all, they ARE making DLC for the game (is it exclusive to Kickstarter backers? I wasn't sure about that...), so I know they're going to keep going back to it for the time being. Now I'm REALLY looking forward to this game!