We're working on making the Toolkit home page better, and one of the things we're going to add is a showcase showing some great sites using the Toolkit. The showcase will be very similar to what you see for the ASP.NET AJAX showcase that's already there, Kirti has all the details on her blog. She's got instructions for how to submit.
We're already getting submissions, so get yours in. We'll pick the best and put them up for our showcase. It's a great way to draw some more traffic to your website!