What are the commas in my /etc/passwd file?

Some tool you used to create the account (adduser?) added them. The tool in question sees the comment / real name field in the passwd file as a GECOS field:

http://en.wikipedia.org/wiki/Gecos_field

The field values are

1. User's full name (or application name, if the account is for a program)
2. Building and room number or contact person
3. Office telephone number
4. Any other contact information (pager number, fax, etc.)

However, I cannot think of an applicaton which uses them. I believe these fields are close to useless. Use a different tool for adding users (useradd?) or explicitely give a value for the GECOS field if possible.