x86_64 version won't install on Ubuntu 7.0.4 64 bit

I'm running Ubuntu 7.0.4 64 bit.  I downloaded the file

    VMware-workstation-6.0.0-45731,x86_64.tar.gz

When I run the vmware-install.pl I get this message:

This version of "VMware Workstation" is incompatible with this operating

system.  Please install the "i386" version of this program instead.

What is the x86_64 bit version for if not for 68 bit Linux distributions?

Do I give up anything by going to the i386 version?

Thanks.

Dean