I guess I don't want to say too much until I know more people have seen it
I enjoyed it. Like with most Marvel movies, I wasn't blown away or anything, but I think this is one of the stronger entries into the MCU, and it's largely because of Thanos. Felt like the first time there was ever truly anything at stake for the heroes, and that's because Thanos was a badass villain. He didn't have motivations for world domination or anything like that, which instantly made him more appealing than the vast majority of other villains we tend to get in these movies. And Josh Brolin did a great job with him.
There were, as always, jokes that didn't land (most involving the Guardians, which is already by far the weakest Marvel franchise IMO), and it felt a little overlong sometimes. But in general I think they handled it quite well given the scope, and it felt like there was some good payoff to the stories they've been building. Interested to see how they handle the next one.