I'm amazed how often I find the words Web 2.0 and AJAX in the product requirements of late. These are NOT requirements. They are buzzwords. Take a look at the mostly widely successful websites of late (MySpace, YouTube). None of them are very Web 2.0 savvy and there are few actual uses of AJAX. Web 2.0 and AJAX are cool and can make a website more usable in places, but building a business on buzzwords like Web 2.0 sounds like building toilet bowls.