The tech and media savvy hipsters currently at SXSW could very well be a snapshot of things to come. The conference is chock full of smartphones, but there's nary a notebook (or netbook) in sight.
It's anecdotal evidence, sure, but these folks are undoubtedly ahead of the curve on technology. And what they're saying is they're more comfortable using mobile devices as a primary computing and communications tool than they are with notebooks, or even netbooks.
[Notebooks are] still here, but are far fewer. Right now I can see several open tables and an entire open outlet. Instead people are clustered around mobile phones, showing off applications, photos or videos. You can see little clusters of them dotting the halls, like this group I photographed here. I've even seen one or two people charging their iPhones, rather than charging notebooks, in an outlet. As for netbooks, I haven't seen many at all. - Stacey Higginbotham, GigaOM
GigaOM notes, and I agree, that this is not the End Times for notebooks. It just means people are much more comfortable with using their phone as a computing/communication tool than they were the year before. Expect that to continue as phones get even more robust and the networks get faster.