The most exciting thing that I have seen recently has been the adoption of opneid by the large portals. Not only do I really like the simplicity of openid I like that no one really owns all the ids. Lets see what else gets created and how long it takes before a bank will allow you to use an openid account to manage your bank account.
I already have a few ideas about some neat features for openid and how a user can maintaain control of where the id is used. I am researching to see if I can create them and get some street cred before I just announce it on my blog and let AOL steal it and pretend they invented it.
If you are not familiar with open id you probably aren't really into blogs, but please google the open id organization and get familiar with it. I think it holds much more promise than MS CardSpace or Liberty Alliance.
The problem with SAML assertions to me are all the extra stuff that has to be done to make it work. Stuff is a techinical term for requiring company agreements on SLA, and who is in who's circle of trust. ITs just too much in my opinion to ever really be adopted on the open internet.
Its the simplicity of Open ID that makes it so nice.