It is a legitimate conference. That doesn't mean it's any good. It doesn't have any standing in the AI or machine learning research community (unlike: NIPS, ICML, AAAI, KDD, CVPR, ACL, etc...). The Springer LNCS series is just an oddball mishmash of papers from all sorts of sources. A legitimate publication, but not one with any standing in the community.
It's unfortunate that which conferences/journals are "good" (e.g. worth reading) or not is one of those things that's really 100% obvious to anyone in the research community, and totally esoteric to anyone not in the community.
Major thread bump here, but there are a number of (second) authors of papers that are recognizable and credible ML/AI researchers. In particular I noticed Marcus Hutter and Jürgen Schmidhuber.
It's unfortunate that which conferences/journals are "good" (e.g. worth reading) or not is one of those things that's really 100% obvious to anyone in the research community, and totally esoteric to anyone not in the community.