WebGL Support Begins to Arrive in WebKit
Wolfire Games' blog reveals that WebGL has quietly been integrated into the latest WebKit sources. WebGL is a standards based initiative which is bringing hardware accelerated 3D graphics to web browsers without the need for browser plug-ins.
Opera, Mozilla and Google have already committed to WebGL and the inclusion of it in WebKit means it should eventually trickle down into Safari as well. These demos show them running in early versions of WebKit/Safari.
Wolfire speculates that if it gains widespread adoption, "full-fledged 3d video games" could becoming more common on the web. Like many of the other emerging web technologies, this could threaten to dislodge Adobe's Flash technology.
WebGL is not yet available in the nightly builds of Webkit and is currently only available if you compile the source yourself.