I saw Kingdom of Heaven and liked it well enough. It wasn't as good as Gladiator but it was better than Troy.
If you're looking for an accurate historical account of the Crusades or religious attitudes at the time, this probably isn't the movie for you. But if you like old-fashioned period films with studly guys, gorgeous locations, phenomenal sets and beautifully detailed clothes, then this movie is a good bet.
The story isn't perfect (especially when it comes to Orlando Bloom's motivations in the movie) but Bloom is easy on the eyes and there's plenty of spectacle. Look out for a nice performance by Edward Norton as the leper King Baldwin of Jerusalem.
Ridley Scott has said that the version in theaters (2 hrs 25 mins) isn't the version he wanted to release. Apparently, he wants to release a 3 hrs 30 mins version on DVD. This might help with some of the storyline issues as it definitely seemed like things were missing.