[flexcomponents] Flex 4.0.0.6192 Namespaces

[Baz]

I've been playing around with Flex 4 (build 6192) and it seems that the
namespaces have changed a lot since previous builds. I only say this because
none of the examples online seem to work. After lots of mucking around, I
was able to get the following test application with these namespaces to run:

<?xml version="1.0" encoding="utf-8"?>
<fx:Application
    xmlns="http://ns.adobe.com/mxml/2009";
    xmlns:fx="library://ns.adobe.com/flex/spark"
    xmlns:mx="library://ns.adobe.com/flex/halo">

    <mx:VBox>
        <fx:Button label="Gumbo Button"/>
        <mx:Button label="Halo Button" />

       <fx:ButtonBar id="orangeToggleBar" requiresSelection="true">
            <fx:dataProvider>
                <fx:ArrayCollection source="[Flash, Director, Catalyst,
ColdFusion]" />
            </fx:dataProvider>
        </fx:ButtonBar>
    </mx:VBox>
</fx:Application>

The FX namespace pointing to spark doesn't seem to be right, shouldn't it be
SP or S with FX as a separate space? Also, what about the
ns.adobe.com/flex/GUMBO library, is that gone? I saw it a lot online but I
think it may have been combined into the main (unnamed) namespace, what do
you think?

Cheers,
Baz