No sooner has the Windows Live Wave 2 suite been released than the first Wave 3 beta begins - Windows Live Messenger v9. Unlike the betas that have just finished, the Messenger v9 beta is being run from Microsoft Connect as a private beta, meaning that, for the moment at least, unless you receive an invite, you won't be able to participate.
For the moment it looks like most previous Windows Live testers are getting invites, so stay tuned to your inbox. With such a popular beta like this, you better sign up quick.
So what's new? While the goodies aren't yet available, we've heard about Multiple Points Of Presence (MPOP) support, which allows you to sign in from multiple devices, ie be online at two places at once.
Link: Feature List (according to a Neowin Blogger)