On this blog and in other contexts I've said that IMS is important because if adopted widely it would allow for all the billing glory that the telcos are looking for.

It's a formless thing, though, this IMS, but I understand that it includes use of SIP as the signaling standard.  That's a very telco standard.

I'm wondering if readers of this blog have links to useful resources about IMS and its adoption that would be helpful to a general audience.  I'll also be looking around, but the collective undoubtedly knows more about this than I do.  I'll post links here that you tell me about.