Walking out of the theater, I felt that I kind of got it, but I kind of didn't. I talked it over with my wife on the way home and then I watched the RedLetterMedia review and understood what they were going for and it made a little more sense.
I don't want to spoil anyone, but if you're going to see this, I think it would help having a general knowledge of the real world events involving Charles Manson and Sharon Tate. Detailed knowledge isn't crucial but the movie assumes you have some knowledge, because it won't be explained to you. Those real life events serve as the movie's backdrop and what's at the forefront is story of Rick Dalton (DiCaprio) and Cliff Booth (Pitt). From there, this movie is essentially Tarantino's take on a fairy-tale.
The acting in this movie does not disappoint even when it's meant to be on display due to the meta nature when the movie is a film within a film. The line between the actor's reality and our reality is walked with precision and expertise. There are a few scenes that go on a little long where I was wondering what the point was, but I chalked it up to quality time spent with these characters so we end up caring about them, otherwise the final act wouldn't work.
Also, I learned that from the aforementioned review that Tarantino took a lot of time to re-create 1960s Hollywood and use a minimum about of digital effects as possible. Personally, I guess it felt like 1960s Hollywood, but as a non native I didn't appreciate it as much as maybe a native would. I know "La La Land" got a lot of praise for its treatment of Hollywood and since I don't have that extensive background of that area and/or era, it was just that - background. I cared more about the characters and plot than I did about Cliff driving around for 5 minutes. Although, it was nice to see the driving and feel the time it took to get from point A to point B instead of it feeling like insta-travel.
Overall, this wasn't my favorite Tarantino film, but I have a good appreciation for it. I loved the scenes where he expertly created tension as those sucked me in and had me at the edge of my seat. He does that very well and the payoff definitely comes later so you have to have the patience for it going in hence why I didn't see this movie opening weekend and waited until I was prepared to go on the journey.