I think that the weblog phenomenon is, on some level, a reaction to USENET (and to some degree mailing lists) becomming unusable due to spam. Even if most of the people writing weblogs have never come closer to something that implements nntp than having an unnoticed copy of Outlook Express on their hard drive, if USENET hadn't been killed by the green card lawyers' followers, they'd be using it today.
It is also possible, of course, that I'm undervaluing the allure of having a site that looks the way you want it to, with only your words on it.
Unrelatedly, someone needs to figure out a way to build a PDA and a phone into a wallet. There's plenty of room for user interface, it just needs to be kind of squishy, hold credit cards and cash, and be able to survive being sat on.
