The Windows Live Custom Domains team just launched version 2.0 featuring the new Wave 2 UI and a bunch of new features.
According to their team blog the highlights of this release are:
E-Mail optional domains: Your can now register a domain to host Windows Live IDs without the need to change the email provider still allowing for Windows Live Messenger use
Custom Adresses: You can now set up friendly names under your domain (eg. mail.liveside.net) that point to the Windows Live service
The default member limit has been raised to 500 (it was previously at 100) and can still be extended by request
An updated SDK with twice the number of methods and richer sample apps
Go and give Custom Domains a test run…..