Personal frustrations aside, the marketimg strategy makes perfect sense to me. Needs to be late enough to minimise competitor imitation and prolong a "first to market" period. Needs to be early enough not to compete with christmas marketing - which ramps up exponentially from November.
There are other considerations, such as not wanting to have a negative impact on other nintendo sales (and to a lesser extent, wanting a negative impact on competitor product sales), but i won't go into detail.
FYI stocks go up and down constantly, nintendos stocks rocketed following their announcement of an impending announcement. It would have been a genuine shock if it hadn't gone back down after the trailer was released.







