Those aren't two interpretations of the same piece of news; if Game Informer are to be believed, then two fighting games are currently in development, both pitting the stars of Namco against the stars of Capcom.
Note these are fighting games, not a continuation of the old RPG title that appeared on the previous hardware generation. Why two games? Simple: each company makes one! Capcom would be developing Capcom vs Namco, built on the Street Fighter IV engine, while Namco will develop Namco vs Capcom, which will run on the Tekken 6 engine.
As fighting game fans are already no doubt understanding, this would mean two significantly different fighting games, Street Fighter IV's 2D arenas contrasted with Tekken's full-blown 3D combat.
GI say that Street Fighter IV producer Yoshinori Ono is producing Capcom's side of the deal, while it's expected Namco Bandai's Katsuhiro Harada will be in charge of the opposite project.
If this information is good, then the two games' debut trailers will be shown this weekend at the San Diego Comic-Con.
Namco Vs. Capcom Not One, But Two Games? [Game Informer]