I doubt Tapestry is on Microsoft's radar. It's on the
JSF team's radar, though.
There are, after all, only so many ways to skin a cat. From what I can see about WebForms, it isn't as rich as Tapestry in many ways; for example, it requires client-side JavaScript, all links are actually form submissions in disguise and (correct me if I'm wrong) each page can only have a single form.
Tapestry allows real links, many forms per page, highly dynamic forms (i.e., with looping, such as within an e-commerce shopping cart) and much more.
--<br />Howard M. Lewis Ship<br />Independent J2EE / Open-Source Java Consultant<br />Creator, Jakarta Tapestry<br />Creator, Jakarta HiveMind<br /><a href="http://howardlewisship.com" target="_blank" rel="nofollow">http://howardlewisship.com</a>