The patches above all have the same problem: when the customer goes to write a review, the page has a big heading - "Written by Joe Blow"
So any customer who does not want his full name used on a review will be scared off by seeing his full name.
There's a simple solution - /includes/templates/template_default/templates/tpl_product_reviews_write_default.php
Copy this file to your template folder i.e. /includes/templates/YOUR_TEMPLATE/templates/tpl_product_reviews_write_default.php
About line 40 - change this line:
<h3 id="reviewsWriteReviewer" class=""><?php echo SUB_TITLE_FROM, zen_output_string_protected($customer->fields['customers_firstname'] . ' ' . $customer->fields['customers_lastname']); ?></h3>
to this:
<h3 id="reviewsWriteReviewer" class=""><?php echo SUB_TITLE_FROM, zen_output_string_protected($customer->fields['customers_firstname'] . ' ' . $customer->fields['customers_lastname']{0} . '.'); ?></h3>
This truncates the last name to the first initial and adds a period.
Now the write a review page shows "Written by Joe B."
When you get a new review, go into the database and change the name on the review to Joe B.