What primarily needs to be noted here is that it is brilliant as a work of art, and not only as a piece of entertainment. It is clearly a traditional cinema movie, not an "anime" of the type Westerner is accustomed to. As such you shouldn't expect almost any typical elements you learned to adore in the works you treasure in your anime list. It's also not advisable to judge the movie by classical MAL categories, especially in "Story" and "Character" sections. "Sennen Joyuu" doesn't tell any substantial story. Ok, it does, to a degree, it can be potentially described as simplistic yet gripping romance melodrama. And I saw the movie advertised that way by many people. But it is doing the movie a great injustice, because simplistic story is certainly not its main goal.
The movie is rather an unusually skillful meta-narrative, it is the story about stories, tropes and plot devices, about what role they play in each individual's life and how powerful driving force they can be, despite being simplistic. And it focuses on very specific types of stories - on these told using cinema as a medium, thus on numerous different cinema genres at once. As such film "Millennium actress" pays homage to many (mostly Japanese, but not only) movies. While it is not necessary to pick up references to these films, if one is able to pick at least some of them (fortunately some will be rather obvious) it enhances the viewers' enjoyment. On a side note - Japanese cinematic references notwithstanding, it's probably the most culturally Western anime I've ever watched, second being, by peculiar coincidence, Paprika by the same director.
The movie doesn't indulge itself in character portrayal much either - you shouldn't expect captivating protagonists or antagonists or development thereof. Or again, to an extent you should, because, as I noted before, on the surface level it's the story about the journey in search of love. But as a meta-movie it's more about how the character is created (or how she creates herself) in act of being portrayed.
"Millennium actress" is also kind of an ironic proof that anime is sort of ghetto medium. The movie is apparently in love with "cinema" as a whole, even more with "live action cinema" than specifically with "animation", yet it itself is animation. And I'm afraid it's the main reason it's not as notable as it could be.
But what it's so great about "Millenium actress" that it should be so notable? What comes to mind immediately - It is told by using intertwining layers of different narratives coming from different movies thrown together into individual scenes in an exceptionally masterful way. Every passage from scene to scene, from layer to layer and simultaneously from style to style is smooth and barely noticeable, yet with every turn it creates entirely different reality. And through different turns the story remains coherent and never looses itself on anything unneeded. What's interesting, these ever-changing sceneries gave the creators chance to make the movie even casually entertaining - it contains for example genuine action sequences and even comedic reliefs. That combined with all these setting changes practically excludes possibility of boredom.
Art style closely follows every turn of the scenery - it recreates all different movie genres in their own unique style, often adding some distinctive touch. It's creative and pure pleasure to watch. The soundtrack of "Millennium actress" may be not as infinitely exceptional as the whole movie but still it is pretty much perfect. It resonates with the viewer, it fits the mood of the scenes and it stays in the head after ending.
The movie has also the trait of being simple yet complex. My analysis of the movie is not necessarily the single correct one, the movie stays open to many others. The film provokes the viewer to come up with her own interpretation, without forcing anything on her. Yet it's not vaguely about everything and it gives the viewer strong sense of fulfillment.
The only flaw one could find in the movie is that its unrestricted love for cinema results in film being in love with itself and becoming self-absorbed in playing with different settings and references to other famous works. The movie is by no means bombastic in it, so I didn't find it pretentious. But still, someone could complain about it. And one can possibly call such type of film parasitic or even fundamentally empty - it's not great on its own, its greatness manifests when it plays with genres and conventions, when it builds its world, its story and its moral from borrowed pieces.
Although I'd understand such objections I personally don't regard such flaws as diminishing my final reception. I think that they are inevitable consequences of creator's choices, of what this movie intends to be. I find such movies important and I cherish them immensely. I mention these para-flaws as a warning for people who don't particularly like post-modern self-obsessed meta-narratives - they definitely won't find in "Millenium Actress" anything worth special acclaim. For all the others - it's truly magnificent. Check it out ASAP.
