The stupidity of some people can hardly be blamed on the author of the book.

isn't science must be the new intellectual attack cliché.

Would someone care to define this proper science?

Here's a working definition for you: the construction of interlinked models that are proven/disproven by repeatable independent experiments. Science is tentative and falsifiable. The normal day-to-day scientist usually deals with somewhat boring measurements and experiments inside of a paradigm. Every now and then the paradigm is shown to be broken and a new paradigm takes its place.

Usually to call something "not science" is to say it is not based on 1) testable, falsifiable hypothesis, 2) accurate data, or 3) an inability to replicate/verify

I don't know about Gladwell's book (it sounds rather good actually), but I think officially science is defined via testable hypothesises and their tests. Maybe Wikipedia could help?