my recollection from when I read into this a while ago was that he seemed to omit a number of notable features of China that would likely be remarkable to him. Notably, the great wall (which some think his journey should have taken him past), chopsticks (which were used at the time), kanji, etc.
The thought is that much of it will have been based on hearsay - he heard stories of paper money and Kubla Kahn, but as these stories from fellow travellers did not refer to things like the writing system he never knew to mention it.
Worth noting is that his is a far more accurate record, including several rejections of previous myths about china from earlier sources (porcelain is not made from coal, the Mongols are not elves, he got a bunch of rivers right that previous travellers had gotten wrong).
This is the general gist of the controversy.
As far as Silk Roads scholars are concerned, he did. Rustichello may well have exaggerated Polo’s story, as he was a popular romance writer of the time, but Polo’s general information lines up with the historical record. He includes details about the cultures the Polos came into contact with during their journey, as well as economic details like currency conversions and purchasing habits of local populations that a merchant family would take note of. His geographic information lines up with the historical record, and he includes information like population and military sizes, the food and clothing of each city/culture the Polos interacted with, and how to bargain in those cities. All things a merchant family would be familiar with from actually traveling through those areas.
The best rebuttal of Frances Wood’s claim is Igor Rachelwitz’s, accessible here:http://altaica.ru/LIBRARY/rachewiltz/Rachewiltz_Marco%20Polo%20went%20to%20China%201997.pdf
You may also be interest in this: http://www.history.ac.uk/reviews/review/1667
And this:http://afe.easia.columbia.edu/mongols/pop/polo/mp_essay.htm
(Edit for full name of author for Did Marco Polo Go to China?, the book that kicked off the current run of this controversy in the 90s.)