My suggestion would be to either add some sort of watermark to the thumbnails, or an attribution link to pages that use the free version. This way just isn't going to fly. STW should indeed get some sort of attribution for a free service, but this is excessive.

Boonex does the same thing for free licenses. You have your name on flash apps. If every time a dolphin site user clicked on a video, and landed on a page on boonex.com that touted "you are about to view a video made possible by see more boonex software. Click here to proceed to video ", how well do you think that would go over?

Funny thing is, had stw came up with a less obtrusive attribution, I would likely have upgraded to a paid version. However, when someone tries to cram something down my throat, no way I'm rewarding them with my business.

Get stw to come up with something less invasive, and it will be better received. Alternatively, you can just do nothing, and deal with the backlash whenever you release 7.1. Sooner or later, you'll have to deal with it.