The training itself works just as well as it did back then - the exercises haven't suddenly become ineffective just because the DVD is older. What's changed is more the availability and flexibility: on YouTube you'll find thousands of free options, you can pause whenever you want without having to dig out the DVD, and these days there are trainers who've incorporated newer knowledge (better form cues, less injury risk and stuff like that). If you enjoy working out with the Jillian Michaels DVDs and do them regularly, I'd just stick with them - consistency matters more than whether the videos are from 2010 or 2024. But try a YouTube video sometime too, maybe you'll like that format better.