At anyrate, Mark has been showing me some of the upcoming new features around WebORB going forward and I'm really impressed with the level of effort and work that he and his team have put in.
Adobe aren't looking to support .NET per say in terms of Flex integration (Aside from WebService/XML which this post shows as marginally slower), and when asked at WebDU about this, Tim Buntel essentially stated that developers would be most likely better off using Coldfusion 8 as the broker between .NET and Flex (Adobe indicated they are working with Mark around WebORB, but Mark has indicated that the relationship is kept at 'arms-length' - so not sure whats going on there).
Figure 1.0 - A breakdown of the WebORB stack.
Given that WebORB works natively with Flex, it's quite feasible to slot this server-side remoting into Apollo, so this is great news for .NET developers whom have a lot of server-side goodness but want to play in the Apollo space.
The other flipside of this coin is that although Adobe's making a lot of positive movements with making Coldfusion 8 talk to .NET natively (which was impressive), you can also use WebORB to talk to Coldfusion and ASP.net depending on your current architecture strategy.
The workflow in terms of building a FLEX application with WebORB is pretty simplistic and at times better then what you'd normally get today in Flex development without WebORB (It had Andrew Shorten and I drooling at how cool and easy it was when we saw it). I say this, as I watched Mark in Seattle drag-n-drop a mx:DataGrid onto the canvas and then through a custom-menu inside Flex Builder 2.0.1, a developer was able to wire up code that talks directly to the .NET server (using Cairngorm code dumps if you want as well).
It's also important to further note, that if FLEX is not your cup of tea, then you can enable WebORB strategy using AJAX, in that Apollo can also provide a homebrew browser experience to AJAX developers (look mah, no flex) and with WebORB it's happy to take over the burden of client-side talking to server-side.
Check out WebORB's documentation around what it can and can't do in terms of empowering Flash Clients & AJAX Clients to .NET server-side while at the same time getting access (value-add here) to Java/Coldfusion.
I've also gotten quite impressed and used to Management Console, which is not only functional but built in the Flash client (so these guys are even dogfooding their own gear).
You can read more on Mark's thoughts about the whole Flex, Apollo, .NET, Java and LiveCycle discussions and what not via his blog (http://www.themidnightcoders.com/blog/)