Personally, I prefer to translate it as "holy", rather than "noble" (or anything similar, like "aristocrat", etc.) because these latter senses are social, which is quite irrelevant to how the Dhamma uses the term.
I suspect that this very early decision amongst western buddhology to use the term "noble" is related to the general overview that they had of the time, ie. the "aryan invader" theory. Despite early linguists who stated explicitly that "aryan" referred to language type, and not ethnic group (let alone social group), still, some continued to portray the Vedic brahmans as "invaders" from the NW, into India, subjugating the other indigenous peoples there (such as the Dravidians). Such a theory was then used to explain the history of India to the Indians themselves, in a manner which then justified the invasion of India by the Europeans. "After all, you brahmins were invaders, now we have invaded you!" The Nazi position is merely the step which made a small twist in theories of groups such as the Theosophists: Whereas at the early times, it was the Vedic brahmins who were the superior people on the planet, overcoming the indigenous black people of India, now the European Aryans have come to claim their place as the superior ethnic group of the present day and age. Theosophy theory of species, race, etc. is complex. The Nazi's did their spin. It was common amongst many philosophical thought movements of that day and age.
This "aryan invader" theory has now largely been debunked amongst scholars. However, because the flow down effect takes a generation or two, and many still read very old and dated material, it is still common.
I shuddered when I encountered a Uni Buddhist prof who trotted this stuff out in "history of Indian Buddhism" as if it were "simple fact", rather than a dated and highly debatable theory. (Made me seriously doubt his scholarship, which was later proven as the course progressed.) It is most strange when it comes from Indians, Sri Lankans, etc. themselves, particularly the older generation who basically have what I call a "Pali text society" mentality, and still live in the latter days of the 19th century colonial Brittania. A bit of serious modern research will soon erase these problems.
Hence, to me, any relation with ethnic group or social group is totally missing the point. The only time I ever use "noble" is for the most entry level classes on Buddhism, where I suspect that people may already be familiar with the term "four noble truths", etc. At the first opportunity though, I introduce the principle of "four holy truths", that which is "true" to those who are holy. Then I wean them out of "noble", and never use the term again. (Fortunately, most of the teaching I do nowadays is either in Chinese, and / or for Chinese, so I can easily point to the Chinese translations, which use mainly 聖 which is much closer to "holy / saintly" than "noble", or 正 "correct", also used for "samyak". Another case of how the choice of terms by classic Chinese translators can give us insight into how the terms were understood by the Indic scholars themselves at that time.)
Some may argue against the term "holy" on the grounds of borrowing from Christianity, but I'd take that any day when compared to the fascist racial theories of some forms of early European Buddhology, and the twisted ideologies which followed in their wake.
Or, better still, I just leave the term as "aryan". It is quite curious, that this term "aryan" and also the good old srivatsa (= svastika) itself, is primarly connected with Nazism / Fascism only amongst the West. In Asia, these are so obviously Buddhist / Brahmanic / Jain / etc. that they have almost no negative connotation at all. I have a few young Buddhist friends who wear svastika necklaces in a similar manner as Christians may wear a crucifix on a necklace. It hangs on there in public for all to see. They would be horrified to hear that they are connected to Nazism, so I simply don't mention it, I do not wish to disturb their pure faith in the Triple gem. I think it is time to reclaim these symbols of Buddhism - but in an intelligent and gradual manner, of course!! (My experience in Zuid Afrika (South Africa) indicates that in some places, this may take a while, though. Seems that more than a few neo-Nazis have taken root in that "rainbow nation"! Still, they were always puzzled why the Chinese would use this symbol, as they would be the first object of it's fascist hatred.)