I enjoyed it. As has already been noted, you need to look at it as being very loosely inspired by the story arc from the comics rather than as a straight adaptation.
It has great action scenes and the most twisted depiction of Lex Luthor put on screen to date. Adam Baldwin does a great job voicing Superman. Anne Heche does a very breathy, staccato rendition of Lois Lane's voice, obviously going for a bit of a His Girl Friday vibe. I found it jarring at first, but came to like the performance on a second viewing.