Ben-Hur is one of my favorite movies. I jumped on the Extra Special Collector's Edition Blu-ray or whatever they call it, and I'm glad I did. Every once in a while, I pull it out and watch the chariot race in Extrasuperfuckingwidevision. It's glorious.
That said, after watching it all the way through once, I probably won't again, at least for a while. I'd forgotten how "epic" the movie really is. There's a lot of story, a lot of setup for the initial conflict between Judah and Messala, the slave years, the battle at sea, the escape, the redemption, the chariot race... It's a huge movie, and if someone has decided to trim it down a bit, then that's not necessarily a bad idea. From the trailer, you can see that they've kept all of the key plot points, and at least a passing reference to the Christian angle (remember that the full title of both the book and the movie is "Ben-Hur: A Tale of the Christ"), so I'm not writing this off quite yet.
Also, remember that the epic 1959 version with Charleton Heston was a remake as well. Lew Wallace did the screenplay for both the 1959 version and the original 1925 version.