Book blurbs are bogus baloney, saith the UK Guardian. An excerpt:
Rule one: if it sounds like baloney, it probably is baloney. 'A dark allegory about empathy, nuclear power and contemporary feminism' is not for us. Then there are those danger words. Adjectives to be wary of include: 'intense' (quite boring), 'merciless' (boring), 'unsparing' (very boring) and 'bleak' (unbelievably boring). There is also that lit-crit jargon that says everything and nothing: 'ironic' (up itself ), 'magisterial' (too long), 'surreal' (no plot), 'humane' (turgid), 'complex' (unreadable) and 'picaresque' (pointless). Beware 'masterpiece' (we paid too much for this and it's translated from the Albanian). Watch out for 'momentous' (not a quotable review in sight and the editor responsible has been fired).
I've had my blurbs appear on six or so books myself, and I think I avoided all those words. I hope.