I don't know if I'd go that far, but I do think both titles deserve to do better certainly; I think both will eventually find lifetime totals. IF you ask me, though, I think SH:SM is the better of the two; FFCB is good but not stellar--but again, this is just the first month of sales; let's see how they do in the longrun.
Either way, I don't think this will translate to Konami and Square-Enix jumping ship; both still have projects coming to Wii (the former a racing game I saw on GoNintendo.com, the latter DQX.)