WSJ has a discussion between Todd Dagres and David Hornik:

Mr. Dagres begins: Web 2.0 is a bubble for 3 reasons: 1) There is far too much money chasing Web 2.0 deals. Too much money means too many companies getting funded at higher valuations. 2) There are virtually no barriers to entry in Web 2.0 and therefore the ability to develop a unique solution and sustain a competitive advantage is virtually nil. Therefore, it's difficult for Web 2.0 companies to build long term value. 3) There is very little liquidity in the market for Web 2.0 companies.
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Mr. Hornik responds: I do not believe that the existence of too much venture capital money chasing too few interesting ideas constitutes a bubble. The Web 1.0 bubble inflated because the public markets were willing to bet on unproven ideas. Public markets are ill suited to evaluating such risks. On the other hand, the venture capital community exists precisely to take on that risk. While many Web 2.0 companies will fail, they will not likely fail in significantly greater proportions than has been the case with other venture investments historically.

WSJ writes: "The social-networking revolution is coming to health care, at the same time that new Internet technologies and software programs are making it easier than ever for consumers to find timely, personalized health information online. Patients who once connected mainly through email discussion groups and chat rooms are building more sophisticated virtual communities that enable them to share information about treatment and coping and build a personal network of friends. At the same time, traditional Web sites that once offered cumbersome pages of static data are developing blogs, podcasts, and customized search engines to deliver the most relevant and timely information on health topics."

InfoWorld lists them:

1. More mobile access, more competition
2. The era of 'the big bundle'
3. The democratization of mobile e-mail
4. Search and discovery
5. Mobility gets social
6. Convergence: One phone, many places
7. Media, media, media

Michael Mace thinks much more than just flat-rate data pricing is needed to make mobile data usage take off. Among them:

1. Provide a consistent architecture that works offline. This is probably the most critical need. Web applications depend on having a constant connection between the user's computer and the Internet. That's not practical for the mobile Web. Even in countries with heavy 2G coverage, there are lots of gaps in the 3G network, and will be for many years. Mobile Web apps need to work like RIM's e-mail client, which stores both the program itself and the user's data locally and then sends the data to the network when a connection is available.

That means just bundling a browser is not enough. The phones will also need software installed on-device that can manage applications and data when the user is offline. That could be an operating system like Windows Mobile or Palm or Symbian, it could be an applications layer like Adobe Apollo or Java, or it could be other software that the web community will create if given the chance. This software layer will need to be consistent across phones, just as HTML is consistent across all browsers.

Michael Mace writes about a comment made by Palm CEO Ed Colligan: "The phone is one of the few private spaces left. People may resist intrusions there. The ads will have to be incredibly creative in order to be accepted."

If 2005 saw the rise of Ajax and mashups, then 2006 was the year in which Widgets started coming into their own. David Beisel summarised this nicely:

The real (and largely uncovered) story of 2006 is the emergence of online syndication widgets. I didn’t see the importance of a few simple lines of portable HTML code affecting the online space so dramatically, and I suspect most others didn’t either.

First, it should be said the rise of online video was fueled in part by widgets – YouTube built a good portion of their own traffic through the syndication of their player throughout the net (and especially on MySpace). Many photosharing sites (like Photobucket and Filmloop) similarly based their viral expansion on syndication of their hosted content through widgets on MySpace and other social networks. The success of these services spurred Fox Interactive Media into launching TheSpringBox, a “widget” platform for MySpace users that also works on the desktop. Similarly, Google released Google Gadgets in May, and Yahoo released “the long-awaited Universal binary of the Yahoo! Widget Engine version 3.1.4” that month as well. In my own daily consumption of information, blogs like Widgify and Flying Seeds became staple reading.

Of course, numerous startups got into the mix – rising social networking star Bebo launched “Bebo Widgets” last week, Widgetbox/PostApp provides a directory of widgets, and most of the social shopping sites leverage them for user-expression. Widgets are now the building blocks of the emerging set of personalized start pages. The Chumby promises to expand the reach of our widgets from our computer screen and into the rest of our homes.