@Grant Griffiths - I didn't said you are doing anything illegal. Don't put in my mouth things I didn't said.

I told that you are not totally honest because your GNU/GPL code is useless UNLESS the user buys your CSS and Javascript and obeys to your Terms of Service.

And those Terms of Service is the total opposite of GNU/GPL or even any OSI-compatible license around. It is is fact one of the most closed licenses I saw in WP themes.

Being honest and being illegal are too very different things.

What you are doing is something that I even suggested as a solution for the Thesis and other theme developers to comply with GNU/GPL and, at the same time, circumventing it and close the product. And I also said that that solution is dishonest to the community.

The honest (and legal) approach is to release all the product with GNU/GPL and sell services around it. Or you could even do it like Blender. You could use http://www.kickstarter.com/ to raise the money to release everything under GNU/GPL.