Marvel has suffered tremendously in quality since 2000, IMHO. Mainly because they let profitability change the orientation the stories were told -- namely, the form of the comic book itself -- the 30 pages. Instead of monthly adventures, you have a story arc stretched over 6 issues so a TPB can be turned out. Most titles have suffered because of this format. For example, the Incredible Hulk, who, when asked to build dramatic tension over 2+ issues, he fails. Big Green isn't that interesting especially when you have to recall what he was doing 2 months prior.
Enter X-Factor and Peter David. Former scribe on the Hulk, his writing has not only leaped bounds here, but he best represents what the genre is capable of now. And I do think you have to consider the TPB comic a different animal than the individual comics most of us when we were young. David, who had to deal with editorial BS like multi-comic crossovers, here takes one of the worst, the Civil War, and integrates it with finesse, adding to it (questioning its very premise), throwing it aside, and not letting Civil War interfere with his main narrative thread: X-Factor's uncovering the Tryp family's connection with "Decimation." Even if you don't know what "House of M," Decimation," or "Civil War" mean, you can enjoy this story. David leaves no thread left hanging, yet is able to preserve his main interest in the family squabbles of X-Factor.
What I love about X-Factor is that it is most soap opera with superhero antics entirely in the background. Although I love the powers the characters have (Madrox is surely one of the most interesting Marvel characters in recent years), its their personalities that David gives us. Each has their own speech styles, an emotional range, and non-verbal tics. These are interesting people, superhero or not. The supervillain thread, looming in the background, is just icing on the cake (although particularly delicious icing: Tryp is quite interesting and a formidable villain for a whole team). Why haven't I been reading this title regularly?!? Time to catch up!