OK, it was a start. Unfortunately, this is about as far as most people get. They rarely dig deeper into his further six levels in the cognitive, six different aspects of psychomotor skills and his rather useless three types of affective.
Sliced and diced
Since then we've had dozens of taxonomies which sliced and diced in all sorts of ways. We've had Biggs, Wills, Bateson, Belbin and dozens more. The problem with taxonomies is their attempt to pin down the complexity of cognition in a list of simple categories. In practice, learning doesn’t fall into these neat divisions. It’s a much more complex and messier set of cognitive processes.
Another danger is that crazy instructionalists, like Gagne, take these taxonomies and attempt to design learning that matches these categories, destroying much of the more useful approaches which an understanding of brain science brings; such as cognitive overload, working memory limitations, top-down processing and so on.
Thankfully, brain science has moved on and we have solid theory, especially on memory, which has put everything on a more empirical and scientific basis. Using Bloom is barely more useful than phrenology when actually designing useful learning.
I am now putting on my headguard and body armour.