All QML import plugin targets should follow the same naming convention

Import plugin targets for particles and multimedia are called the same name as the project particles.dll and multimedia.dll. Import plugin targets for webkit and gestures are called project name+qmlplugin: webkitqmlplugin.dll and gesturesqmlplugin.dll. Import plugin target for folderlistmodel is called qml+project name+plugin: qmlfolderlistmodelplugin.dll.

Qt's own QML import plugins can be found under /src/imports

Proposed naming:
webkitqmlplugin
gesturesqmlplugin
folderlistmodelqmlplugin
particlesqmlplugin