The anime is remarkably good. I have read the manga that covers the same period as the series thus far, but the wife has not and still enjoys it. They have, fortunately, completely avoided the need to know the manga to enjoy the anime. This is a common failing. As a matter of fact, I think the anime is superior story-wise. It is a more cohesive tale that seems to be moving to a point of closure that I do not remember from the manga. The stories are funny, and a bit scary. The story arc is not too important, but present. All we do know is that there is something more for Watanuki, and Yuko knows it. She just is not saying.
At roughly twenty-five minutes, the episodes are interesting and fun. Easily some of the better anime. I prefer it to Cowboy Bebop, which is an awesome show. This could be a good choice for non-anime enthusiasts. The only anime the wife watches is Miyazaki films, but she'll watch several episodes of xxxHolic in a sitting. Watch episode one below.