If you're still yelling about "Web 2.0", you're chasing last year's trend (which means that marketdroids chasing after "marketing 2.0" are really behind the curve). Don't take my word for it - Robin Wauters has done the research:
So why do I say it's [ed: searches for "web 2.0"] fading? For one, because the number of startups that contact us and include the term Web 2.0 in the subject line or message is visibly dropping (and that's a good thing), and I hardly ever see it mentioned anymore on other technology blogs and news sites either. That's not really tangible, so I took a look at the number of mentions of the phrase across the web, and they seem to be decreasing significantly, reflecting my feeling on this.
Follow the link for Robin's conclusions, and links to the actual research. In the meantime, it looks like you don't want to pump your product up by using the "Web 2.0" phrase.