Microsoft supporting Silverlight UI automation ... nearly a problem of the past !

UPDATE : Microsoft Coded UI now supports Silverlight 4, thanks to VS2010 Feature Pack 2. Cf http://memoprojects.blogspot.com/2010/11/first-attempts-with-codeduitests-with.html

The problem detailed later is "nearly" solved by Microsoft, here is the Post from today :
http://blogs.msdn.com/b/anutthara/archive/2010/07/14/update-on-silverlight-ui-automation-release.aspx
which indicates that "Silverlight UI automation" CTP is on its way.
The released version is to be by the end of the year.

As for us, in the meantime, we used two complementary tools to record and play automatically our user scenario on our Silverlight 4 application :

A/ QTP (Quick Test Pro from HP) : The post here is quite old, but I can confirm QTP supports Silverlight 4, and we were surprised but pleased that it worked without additional.
I haven't tried the plug-in (it's really expensive) but it is considerably more powerful than our current solution.
B/ Telerik WebUI Test Studio 2010, the version that is integrated within Visual Studio 2010.

Here is the problem we encountered with the Microsoft "Coded UI Tests and Action Recordings" :

1. Run  your  "Test Case" within the "Coded UI Tests and Action Recordings",
2. On an IE 7 or 8 Browser, enter the URL of a web page containing both some HTML and Silverlight,
3. You can perform actions on the HTML part, but as soon as you hit the Silverlight zone, the popup Test Runner - Microsoft Test Manager complains with the following message :
   
   Microsoft Silverlight is currently not supported.
   Go to http://go.microsoft.com/fwlink/?LinkId=157214 for information on available add-in for possible support.
   
4. The "Coded UI Tests and Action Recordings" is paused.