Bought this at Gamersgate, played some MP before in the pre-order window. This may be the best MP experience I've had in years. It's rather fun that a game made by an indie actually supports full dedicated servers, modtools, 64 players MP online and tons of MP modes while big names do an half-ass job.
I rather play this game with its crude gfx than BF:BC2 with its tons of problems. This game in MP is a blast, and that's something I haven't said for a MP game in years.
As for SP, it's much more varied than the original, with romance and being able to build a kingdom yourself, and a new faction, the Saracin Empire, styled after the Saracens. More quests as well, the trade system is still sucky but I'm having more fun in SP than the original.