Nintendo clearly understands the importance of the international economy's fragile supply and demand formula, as evidenced in statements made during a recent investor call. Italian plumbers and pocket monsters are, in the case of Nintendo games, highly sought after properties that are somewhat constrained in supply. The result of this, of course, is high demand for Nintendo's games -- such high demand, in most cases, that third-party game sales on Nintendo's consoles are outstripped by first-party.
Nintendo, however, hopes to appear mindful of stepping on toes. When asked about potential release dates for 3DS versions of Super Mario and Mario Kart, Nintendo head Satoru Iwata noted, "We want the other companies to be successful." He continued, "In order to accomplish this goal, we would like to decide on the dates after we know the release plans of other companies' games so that we are able to consider how we can maximize the sales of our titles without affecting the sales of other companies in the short term."
It's also possible that Iwata is just blowing smoke to avoid answering specific questions about release dates for major franchises, though our mothers always told us not to expect the worst in people.