<p>Is using a handrolled POCO queue class using pseudo code</p>

<pre><code>T Dequeue() {
   lock(syncRoot) { 
      if(queue.Empty) Thread.Wait(); 
   }
}

void Enqueue(T item) {
   queue.Enqueue(item);
   Thread.Notify();
}
</code></pre>

<p>For WCF is request queueing a scalable approach?</p>

Now fixed - the conflict was a difference in Web.config requirements between Preview 5 and Beta 1.  The following needs to be added into the system.web compilation assemblies node:
```
```
<add assembly="System.Web.Mvc, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
```
```
After this change, all of my old HtmlHelper methods magically came back!