Webkit, which powers the layout engine in a majority of browsers such as Google Chrome, Safari, Chromium etc will soon have multi-touch support, thanks to some development work done by Tomeu Vizoso. He is currently working on implementing WC Touch Events API in the Clutter port of Webkit.
Vizoso posted in his blog: -
” Following my past work on multi-touch support in Clutter, have been playing lately in implementing the W3C Touch Events API in the Clutter port of WebKit. A lot of code can be reused from WebCore without problems, but we'll need to do some mildly complex event translation because the W3C API and the one in Clutter (and in XInput and in Gtk+) are very different.”
Vizoso also posted a video which shows its current working.
Hopefully soon, you will be able to use multi-touch in Chrome/Chromium.