If we're talking about the keynote, I'm not sure how much more technical live-blogging could be than the usual suspects: macrumors, engadget(?), etc. They all always blog the announced specs of new stuff, and without a leak or a hands-on, what else could they do?
I just feel that a more dyed-in-the-wool geek is going to be less bombastic about announcements than someone who gets paid on the back of spectacle.
Hopefully Erica Sadun liveblogs it; I think she did it last year, I may be wrong though