Score: Web 2, Kismet 0
The main problem that I see from the Web 2.Overhype is that it seems to be based on a compulsive urge to take randomness, luck, kismet, and all of those other "messy" aspects out of life. (I think that this urge to excise the messy aspects from life is the reason that the Web 2.0 people tout "mashups" as art, rather than learning to paint or sculpt, say - it doesn't require learning how to peacefully co-exist with a medium that has its own characteristics and needs to be manipulated within those constraints in order to work. But that's a rant for another time.)
Take Amazon, for example: If I'm looking for a book on, say, Arthurian literature, I type inm my search terms and up comes a list of books on the subject. I click on one and I get info about that book and other books that I might also be intersted in (tm).
Fair enough... it's efficient, give it that.
Now, let's go to my public library and make the same search: I go to the terminals (since they got rid of the wonderful sensual experience of diving into those wood-and-wax-smelling oak drawers full of file cards... but that's ANOTHER rant for another time!)... so I go to the terminals and pull up a list of books that might be what I want. I take my list of titles and Dewey decimal numbers and head into the stacks. I find those books and, flipping through them, I find the ones that actually are useful to me. But in the meantime, while walking down the aisle to find those books, I've found two books of British archaeology and one on the history of post-Roman Britain and France that puts the Arthurian legends into historical context. ...And Suetonius' "The Twelve Caesars", and Pellegrino's book on Biblical archaeology, which are unrelated to what I originally went in for, but are fascinating reads in their own right, and which I never would have picked up on if I hadn't gone down that aisle, scanning the shelves for the stuff that I originally went in for.
Efficient...? Hell, no - but ultimately more satisfying to me.
There are stores that I go into when I'm looking for a specific item, and there are stores that I go into when I'm looking to see what will present itself to me that I never knew I needed and can't live without (thank you, Archie McPhee, for that phrase!).
Until Web 2.0 can provide me that level of useful inefficiency it will not fully meet my hunting/gathering needs.