The QtWebKit team is currently working on two upcoming releases and below is a quick brief about them:
QtWebKit 2.1 is a release for Nokia platforms (Symbian and MeeGo.) It is used on top of Qt 4.7 and adds a number of bug fixes and features including improved HTML5 media elements support.
QtWebKit 2.2 is a release for all platforms. It is based on a new snapshot of WebKit trunk (that has yet to be taken) and will be bundled with Qt 4.8, but can also be used together with Qt 4.7.
A cautionary note: In preparation for this, support for Qt 4.6 will be removed from WebKit trunk. If you are depending on it then you should contact them to discuss