Yes, that is correct. iWeb was intended for consumers to bang out a home page that can be published to apple's mobile me servers. People took it further and produced some nice sites but the limited number of themes and fairly closed design limited the overall power.
Now that apple has dropped the mobileme services and has more or less killed off iWeb, your best advice is to search for an alternative to creating websites.
I personally use RapidWeaver, it has a ridiculous number of themes and plug-ins. It really puts to shame whats available for iWeb. There are other products as well, but since I work on RW, that's the one I'm most knowledgeable about.