Looking at these statistics might give the impression that web 2.0 is not quite mainstream yet and many would certainly agree. The vast majority of users are still "viewers" rather than "contributors", including in the travel category in which travel 2.0 tools are proliferating at a rapid pace due to the attractiveness of the subject, no doubt.
In most of what might best be described as the b-to-b world, web 2.0 adoption is probably not quite as advanced as in b-to-c, or rather c-to-c. Yes, companies are using YouTube increasingly as a communications tool but it’s still dominated by private users showing off their various creative efforts.
Personally, I don’t really get too hung up on the terminology as it is irrelevant to general users, most of whom are not aware of any difference anyway. For them the web is just getting more useful and easier to use. Those are the factors that will drive adoption and not what name and version number the geekerati give it.