Warning: Review contains spoilers.
I literally just finished watching "Superman: Doomsday" as I type this review.
If you watch this as a stand-alone film, and not try and compare it to the actual "Death of Superman" comic book story then I think you'll thoroughly enjoy "Superman: Doomsday".
The story deviates quite a bit from the 1990s "Death of Superman" comic book story, but I went in knowing that it was simply based/inspired by that story, and wouldn't follow it to a tee.
With that knowledge in mind, the movie was a blast. The discovery of Doomsday, the rampage the monster goes on, the fight with Superman, the world dealing without Superman, the return of a Superman, the world dealing with this new Superman, and the ultimate battle between good and evil Superman, the whole thing was just a great ride.
The were many emotional points that brought a tear to the eye or a lump to the throat. The scene with Martha and Lois, and the final scene with Lois and Superman are two that come to mind.
It took a few minutes for me to accept Adam Baldwin as Superman, but he did a great job. By the end of the movie I was totally convinced. Anne Heche was great as Lois Lane and James Marsters was unrecognizable as himself, playing a calculating Luthor perfectly.
My biggest gripe with the style of this movie is, as many others have noted, Superman's cheeks. I'm not sure what they were going for with this... If it was intended to make Superman look older or more weathered it didn't really work. The lines were just too high to work as indicators of a high cheekbone, and came off as looking more like scars, and were quite distracting at some points in the movie.
Otherwise, the animation was fluid, the lighting was great, the atmosphere was excellent. The designs of the Fortress of Solitude were reflective of both the Silver Age comics, modern comics, the "Superman" movies (with crystal technology) and other animated versions.
Metropolis looked the way Metropolis should, and the Daily Planet building seemed to be reflective of every design from every other era blended into one.
The soundtrack is brilliant. I can understand why they've decided to release it on CD. The main theme isn't like any other Superman theme that has come before it, but it does have elements of other themes within, so it feels right for a Superman movie.
Rating - 4 out of 5: I would highly recommend "Superman: Doomsday" to any Superman fan. Although I'd definitely take heed of the PG-13 rating, as the violence is probably too much for young children.
Don't think of it as an adaptation of the "Death of Superman" comic book story. Think of it as a reinterpretation of that story, created as a 75 minute animated movie.