Krugman may or may not be right on oil prices currently experiencing a speculative bubble. (Which can largely be boiled down to the idea that the actual price of crude oil has diverged from its "fundamental value".) However, he is 100% right that the fundamental value of oil (and other forms of energy) IS increasing, due to rapid growth in India, China and other developing countries.
It's a little late here for me to dissect the article posted by Berigan, but it strikes me that this is largely a mishmash of accusation and doesn't contain many serious arguments.
I would like to say that:
(A) "Speculation" (as commonly understood) is not the same as a "speculative asset bubble". Plenty of speculation can happen in situations where assets trade close to their fundamental values.
(B) "Market manipulation" is different from "speculation" or "speculative asset bubbles". The latter two can happen without any market manipulation whatsoever.