The browser team at Nuanti Ltd. is developing Meta, a brand new WebKit port suited to embedding in OpenGL and 3D applications. The work is being driven by Linden Lab, who are eagerly investigating WebKit for use in Second Life.
We've paid great attention to resolving the technical and practical limitations encountered with other web content engines.

uBrowser running with the WebKit Meta engine
In the run up to our first code drop and SDK preview, we've set up a couple of Google Group where developers can track progress, request features and find out more about Meta.
You can also contact us directly by email at info [at] nuanti [dot] com.
The original announcement blog post contains further details.
Nuanti Ltd. 2008-06-12