Microsoft: Internet Explorer 8 offers Web developers the opportunity to write standards-compliant HTML-based Web pages that support features (such as SVG, XUL, and MathML) in namespaces, provided that the client has installed appropriate handlers for those namespaces via binary behaviors... See Improved Namespace Support white paper for more information.
If I read this correctly, it should be possible for IE-8 to display the SVG that exists on my web page, assuming that the necessary handler is installed and deployed. Microsoft may not be the one providing such a plugin, they are merely asserting that it can be done.
Besides the obvious (namely the fact that there is no standards compliant way to embed SVG in a non-XHTML page), this is very good news. I hope other browsers (and, for that matter, the WHATWG) follow Microsoft’s lead.