Having just returned from a month of living and teaching (in Chinese) on the Mainland (in other words, receiving an intensive dose of Putonghua), I was struck by how different Taiwan Guoyu *sounds* in this video. It's about a subject that is dear to my heart: the medieval caves at the Central Asian site of Dunhuang with their magnificent wall-paintings and multitudinous medieval manuscripts.
Of course, Taiwan Guoyu (National Language, i.e., Mandarin) is still basically the same language as Putonghua (Modern Standard Mandarin [MSM]) on the mainland, but the sounds and a lot of the words and typical expressions are somewhat different (judging not merely from this one short video, but from other samples, both written and spoken, as well). And, of course, the script has radically diverged.
It's sort of like the difference between Hindi and Urdu, which are fundamentally the same language, but with the latter having a larger proportion of Islamic vocabulary (chiefly Persian and Arabic) and some differences in pronunciation. Naturally, Devanagari and Arabic are totally separate scripts, but the *look* of written Taiwan Guoyu and of Mainland Putonghua is also noticeably dissimilar, even to someone who cannot read either of these types of written Mandarin.
W. South Coblin comments on the divergence between Taiwan Mandarin and Mainland Putonghua (PTH):
I think we are all pretty well aware of the differences between Taiwan Mandarin and Mainland PTH, in all the areas you have mentioned. I of course have no first-hand knowledge of the Hindi-Urdu situation. To our Indologist friends I would just say that Taiwan Mandarin has a distinct pronunciation that immediately distinguishes it from Mainland varieties of Modern Standard Chinese. This is because Taiwan Mandarin is most directly derived from the type of Mandarin koiné spoken in the Yangtze Watershed before 1949 and has also been influenced by the pronunciation habits of southern Min and Hakka speakers, who make up the majority of “Native Taiwanese”. In earlier times, and to a considerable extent still today, they have had to acquire Mandarin as a second language. The process of accommodation occasioned by what sociolinguists call “contact convergence”, plus the special origins of the Taiwan variety of the general Chinese koiné, have produced a unique product on the island that understandably differs from what one finds on the Mainland, where the primary basis of Standard Chinese is the speech of general north Chinese, with the sought-after ideal for pronunciation being that of Peking.
I have never heard much about pronunciation differences between Hindi and Urdu. What is usually mentioned in the literature is lexical differences of the sort you in fact allude to…. I suppose one could also talk about morphology and syntax which, again, I have not heard discussed in this connection.
And Philip Lutgendorf remarks on some of the differences between Hindi and Urdu:
Urdu has a number of sounds (such as “z” “f” and a guttural “kh”) that ultimately come from Arabic. Since these are not represented in the Devanagari writing system, slightly modified characters have been developed to represent them (for example, “z” is “j” with a subdot, “f” is ph with a subdot, etc.). Depending on where you go in North India, some people are unable to pronounce them. Thus, in the eastern Gangetic plain, people pronounce the English word “zoo” as “jew” (joo), because they cannot say “z.” Similarly, my first name is pronounced by such people with the “ph” as a true, aspirated labial rather than the “f” sound we use in English!
There are a few other, minor pronunciation differences, but none of this has any effect on mutual intelligibility.
Hindi-Urdu and Serbo-Croatian are acknowledged instances of diglossia and digraphia (I recall that well for Hindi and Urdu from studying them both back in the late 60s and early 70s). Considering their mutual intelligibility, yet distinct differences in pronunciation, vocabulary, orthography, and so forth, one might well ask whether Guoyu-Putonghua on Taiwan and on the Mainland have developed to the state of constituting a diglossia and / or a digraphia. On the other hand, it seems to me that a different sort of digraphia is already emerging on the Mainland, viz., the simultaneous use of pinyin and characters to write MSM. This was a position that was advocated by the late John DeFrancis and is still being championed by the centenarian Zhou Youguang and other script reformers in China, for which see here, here, and here.