What they actually did if you read the paper is:
1) Encode a 6 or 9 image into 2 numbers, based on the number of excess pixels in the left vs right, and top vs bottom quadrants. From the article: After these preprocessing, the two printed image with standard font can be represented by ~x1= (0:9872;0:1595) for character "6" and ~x2= (0:3544;0:9351) for character "9"
2) Use a training algorithm to find the appropriate pulse sequence to give a up result from the molecule's NMR C13 spectra from a 6, and a down signal from a 9.
3) Run the NMR spectrum, feed in pulses based on the parameters produced from pixels encoded in a vector form like 1), get the result of "up" for a 6 and "down" for a 9.
It's certainly neat experimental NMR work, but I don't really see how it's quantum computing. But then maybe that's the NMR spectroscopist in me talking....