I was just in Paris this past weekend. While I didn't stay at this new AC hotel (stayed at Renaissance La Defense) I went by the AC in my wanderings. Some thoughts to consider; none of them big negatives or positives:
- close to the conference center at Porte Maillot, so would certainly be of interest to people attending meetings there;
- near a Metro line (M1, which has the Louvre, Marais, etc. on it);
- near two RER lines (A and C, so direct connections to Chatelet Les Halles and Gare de Lyon);
- surrounded by a mixed neighborhood of residences and business, not as "touristy" as Champs Elysees or Trocedero areas (both pro and con);
- a few blocks from the Bois de Boulogne, so a dedicated jogger/runner, biker, or someone who needs open green space can get their quota (note safety warnings about being in the park at night in case that may be a concern)

After having ridden the RER and Metro back and forth from La Defense, and been subjected to the bland suburban mall atmostphere of that area, I can certainly say that between the two I'd strongly consider the AC, despite the lack of a C lounge!