Using the Goodreads Sync plugin is great, but I have found and have used a small .exe found on Github which is a GREAT addition.
https://github.com/PaulKlinger/Enhance-GoodReads-Export
download your library export .csv from goodreads and point the .exe file to it and let it run.
When you are done you will have columns containing each read date and the genres as well as the counts each genre has AND newly added a feature showing the number of reviews.
Using excel you can maniuplate the final .csv into importable columns to update your Calibre shelves. It's a nice way to get data into your libary that the various plugins may miss without having to re import the metadata for each book individually.
Especially great for keeping track of all the read dates.