That’s the alphanumeric display of time reference, rather than the “going out and meeting someone” type of date.
When I want to put a date reference in the filename of a document on my computer, I most certainly use the ISO version. This is because when the computer sorts by filename, it uses alphabetical/numerical order and doesn’t understand that sometimes numbers are dates. So in order to sort the files so that the datd files come in strict date order, you have to put the biggest time period first (the year), then the next biggest (month), and then the shortest (day). And you can’t use the / character in filenames, so the – character is a good substitute.
In all other formats, I use the British standard 27/02/2013 because this has a linguistic satisfaction to it. The / character is rendered approximately as “of the”. Thus, 27/02/2013 is rendered:
Twenty-seventh day of the Second month of the Two thousand and thirteenth year (of the Christian Era, if we use CE notation – if we go with AD then it’s rendered “year of Our Lord”)
Of course, when speaking, I usually just say the numbers anyway, but the ordering is such that the above construction is implicitly possible. It’s why I actually prefer the US system of listing sporting events by putting the away team first: it has the linguistic satisfaction that you can insert the word “at” to describe the fixture (and indeed, US sports pages typically do just that). The British norm of listing the home team requires a construction “Alpha Athletic at home to Bravo Borough” or similar clumsy form. However, I’ve grown up with the British format so these days I instinctively read the first team as “at home” and the second team as “away”, and have to remind myself it’s the opposite when I check US sports scores.
When speaking, I tend to use “27th (of) February” and February 27(th)” more or less equally, which I think is like the convention of stating sometimes “Twenty-five past two” and sometimes “Two twenty-five” to express the time 14:25 (which as I typed these words is just coming up). I think these forms come about because sometimes it is possible to assume which hour it is, or which month it is, so when someone asks, “What’s the time?” sometimes you can answer just “Twenty-five past”, and when someone asks the date, you can just say “It’s the 27th”. But if the month is important, that information probably has to come first (like the ISO version, you want to narrow it down gradually). Which means that there are even pressures in spoken language for doing it day first or month first. And when was the last time a person asked in seriousness, “What year is this?” outside of time travel science fiction? (Okay, every January forever, I do this, but only as a joke to excuse writing the wrong year on cheques and official documents, necessitating a redo of the whole blasted form!)