StarOffce/StarSuite users think that it is a Sun's product, it is developed by Sun.
OpenOffice.org users and developers think that it is "my," "your" and "our" product, it is developed by "me," "you" and "us."
This is the greatest difference :)
Now we all hope that Sun sells more SO/SS and provides users with good support services, and continues supporting OpenOffice.org the product and the community with resources.
Some prefer SO/SS. Some prefer OpenOffice.org. It's their choice.
You know, there must be countless Office Suite users and prospects on the earth, in the spaces (including Klingon people), in the fantasylands (including Elvish people) and more, whom we have not reached yet :)