In the August 28, 2012 issue of "北京晚报", it is reported that more than a hundred Chinese scholars signed a letter sent to the Chinese government claiming that the de facto official Chinese dictionary 《现代汉语词典》 is illegal to include 239 words which begin with a letter of a western language, violating certain laws that govern the correct usage of the Chinese language. "NBA" is among the words. This news was followed by intense debate on the Internet (, , , , to name the first few). The scholars worry that gradual introduction of 字母词 or letter-words will eventually cause harm to the Chinese language, calling it "the most serious damage since the Chinese character Latinization (Romanization) initiated a hundred years ago". The pro-letter-word side of the argument claims that the Chinese language has been evolving all the time for thousands of years, and that introducing "NBA", "PM2.5", and other letter-words into the most popular dictionary helps the general public easily understand these terms which are already widely used. When CCTV changed "NBA" to "美职篮" (literally "US professional basketball"), the Chinese NBA viewers simply ignore the term and continue to say "NBA" in conversation. CCTV changed back to "NBA" as soon as the Chinese dictionary was published, semi-officially approving "NBA" as an acceptable word in the Chinese language, and more than raising the eyebrows of a handful of die-hard Chinese language scholars.
To be fair, a dictionary of a spelling language (language whose writing system is alphabet-based) never lists a Chinese word as is. An English dictionary never has a non-Latin spelling entry, thus excluding not just Chinese, but any Oriental language, Hindi, Arabic, any Slavic language, and many others as well. To incorporate "饺子" into an English dictionary, the spelling "jiaozi" is used. Now, if we need to have this "symmetry", we must add to the Chinese dictionary a Chinese-character-transliterated word such as "摁逼诶" in place of "NBA". It looks funny though. Why? I guess it's because the users of the word "NBA" in China are used to it and appreciate its simplicity. (How long do your eyes stay on "摁逼诶" for your brain to process the same info as "NBA", even if your native language is Chinese?) If this had happened a century ago, "摁逼诶" would most likely have been accepted in preference to "NBA". But nowadays the Chinese audience of "NBA" are at least able to pronounce English letters. The beauty of simplicity rules. Considering the law of survival of the fittest almost equally applicable to linguistics, I don't see a bright future for "摁逼诶" or any other transliteration.
Hence the dilemma between two rules: the established rule of dictionary compilation, and the situational usage of a word in the population. Because a Chinese character is intrinsically more difficult than a Latin-based word, incorporating "jiaozi" instead of "饺子" in a dictionary of Latin-based language is natural. But on the Chinese language side, the two rules are having a tug of war. Leaving "NBA" or any letter-word out of the Chinese dictionary retains its purity but increases inconvenience of a general reader -- he has to consult another dictionary. The awkward "摁逼诶" in the dictionary would be useless because nobody and no media would likely adopt that spelling.
My take on this: The Chinese dictionary can have an appendix listing the commonly used letter-words, without not yet accepted Chinese transliterations ("麦当劳" is OK but "摁逼诶" is not). It avoids the dilemma by explicitly stating that these words are not Chinese and yet they frequently occur in Chinese text. Inclusion of them is merely for the convenience of readers.
P.S. With the ubiquity of the Internet, this debate may become irrelevant and eventually forgotten, as the Chinese readers that care about "NBA" or any letter-word have easier access to the web for the meaning of the word than the paper-based dictionary. Although this particular dictionary, with no online version, serves as a prescriptive guide in mainland China, its definition of the letter-words may not be as authoritative as the scholars wish it would be.