To "miss the boat" is to fail to take advantage of an opportunity. The phrasal verb "to miss out" has a similar meaning without any reference to boats. As cruise ships sail on fixed schedules, to miss the boat is an expensive mistake!
Example: Lisa: "I missed the boat on the whole iPad things. Are they any good?" Sarah: "Depends what you want to do with them."
This implies that when iPads were first unveiled, to great fanfare and popularity, Lisa did not purchase one; and, even as the fanfare died down somewhat, she did not purchase one later, either. This also implies that she has not purchased one as of this time. This is why she is asking another woman whether iPads are worth buying. (This blog holds no opinion as to what the proper answer is!)