As the results are about to come out, I figured I'd share my personal favorite before the real winners are out there.
The game I had enjoyed the most out of all the 40+ games I've rated, is definitely this:
Super Kaiju Dunk City
https://ldjam.com/events/ludum-dare/38/super-kaiju-dunk-city
Mechanically, it's a pretty standard rhythm game, but everything about it has just been done so well. The audio is great, the graphics are both well made and stylistically awesome, and the controls have just the level of tightness that a rhythm game needs. The difficulty keeps amping up too, and it feels very satisfying when you nail it. The game just feels really good to play, and it's probably the only LD38 game I've found myself wanting to go back and play more.
I'm just really impressed with how thoroughly well done this game is. It of course helps that they were a large team, but clearly they're a team that know their stuff.
Obviously I urge everyone to keep helping out the games in the danger filter, but if you find yourself having the time, go check out this awesome game!