Windows SharePoint Services SP2 has been released - includes a number of hotfixes and security updates but also
Maurice wrote an excellent FAQ about WSS and SP2:
With WSS SP2, will the SharePoint worker process run in Asp.net v2.0?
Yes, it can. Alternatively, you are not forced to use Asp.net v2.0.
Can I use Whidbey Web Parts on WSS SP2?
No. Out of the box, WSS will not use any Asp.net v2.0 constructs. At the core level, SP2 will not change the rendering behavior of WSS. In other words, WSS will not suddenly gain the ability to use master pages or Whidbey web parts. If you wish to use Asp.net v2.0 web parts in WSS SP2, you will need to build your own shim that allows the v2 web part framework to load and interact with the Whidbey Web Parts. Otherwise, you will have to wait until v3 where such behavior is the default.
What is Mike alluding to about being able to use Whidbey Web Parts in SP2?
Stay tuned! It's all about extending the WSS platform (as noted above)... :-)
What is the advantage of running my virtual server in Asp.net v2.0?
Once youre running in the v2.0 space, the corresponding CLR libraries are available. Your code will be able to take advantage of new features as well as the security and performance enhancements found in the new runtime.
If my my virtual server continues to run in Asp.net v1.1, can my code another assembly which was been compiled in .Net v2.0?
No. CLR fundamentals state that you can't "upstream" the clr version from the current running version. In other words, if you decide to run with v1.1, you are limited to loading/working with assemblies compiled with v1.1 or less.
If my virtual server runs in Asp.net v2.0, will my web part code need to be recompiled?
No. This is basically the reverse scenario of the last question; but the answer is not the same. "Downstream" is possible; therefore, any existing 1.x compiled assemblies should continue to work.
Can I create a virtual server/directory that runs in Asp.net v2.0 and have my Asp.net v1.1 WSS site call into the pages and web services exposed by the Asp.net v2.0 site?
Will I need to specify assembly redirection or runtime information for my web part assemblies?
Will I need to specify assembly redirection or runtime information anywhere else?
Yes. If you wish to deploy web part packages that contain clr v2.0 compiled web part assemblies (i.e. SharePoint web parts compiled using the new clr), you will need to create a *.config file for stsadm.exe that specifies the following:
<?xml version="1.0" encoding="utf-8" ?>
<supportedRuntime version="v2.0.50727" />
<supportedRuntime version="v1.1.4322" />
The config file (appropriately named stsadm.exe.config) will need to be placed next to stsadm.exe. If you don't add the config file, you will get an error message that states "Version 1.1 is not a compatible version".
Can my SPS server run on Asp.net v2.0?
No. See the "Bad News" section of Mike's post - Web Part Interoperability the good news and the bad.