And if you're a fan of usability expert Jakob Nielsen (a favorite author of mine), why not review a few of his articles, including Top Ten Web Design Mistakes of 2005 where he mentions Web 2.0 in passing:
This year's list of top problems clearly proves the need to get back to Web design basics. There's much talk about new fancy "Web 2.0" features on the Internet industry's mailing lists and websites, as well as at conferences. But users don't care about technology and don't especially want new features. They just want quality improvements in the basics.
You really must read the entire article! And while you're at his site, take a look at Durability of Usability Guidelines where he rightly points out that basic usability features don't change all that much over decades.
If you want to delve a lot further into some other peoples' opinion on all this Web 2.0 and blogging stuff, then take a look at Andrew Keen's Web 2.0 - The second generation of the Internet has arrived. It's worse than you think or Nicholas Carr's The new narcissism or Neil Ward-Dutton's Ecosystem vs egosystem to quote just a few.