Single Sign-on (SSO) for the Internet: Weird or Logical

The Internet has become a part of life for many and I am one of them. I use various services available on the Internet like e-mails, SN Sites, Tech new sites, Search sites, Blogging sites etc etc. To list a few which I use:

1) Gmail for collaboration
2) Rediff mail for Job searches etc
3) Yahoo mail for close friends and financial activities
4) TechTribe, Technocrati for Networking
5) Blogspot for Blogging
6) Microsoft and Sun websites for my Job related activities

I guess, most of us use 10 or more sites frequently for various reasons. Most of these sites require some form of identity typically comprising of user ids and passwords and profile information. As an aware user, I know that I should keep on changing the passwords. This requires me to go through all the websites and change it. Additionally, if I need to update my profile or similar info, I have to repeat the same thing and quite a number of times; I avoid doing that because that's a cumbersome process.

A Single sign-on (SSO) and unified view on the Internet will solve the problem. You just need to have access to one site which in turn will manage identity and authorization to other websites. The SSO and UV have been enterprise level solutions for many years and can it be extended to Internet, the extended enterprise. Am I sounding weird or it makes sense? Well this is one of the thoughts came across to me and I have put it across. I understand that are serious issues involved in this:

1) The trust relationship between these websites addressing the privacy issue of users.

2) The mutually beneficial business model and hence the motivation

But I believe Portals like Rediff and Yahoo are in the best position to resolve these problems however they need to share a part of their revenues in order to achieve that. In return, they can get increased traffic and more revenues.

~Cheers
Abhishek