FinDom is the shorthand for FINANCIAL DOMINATION (or for financial dominant/dominatrix). A power exchange fetish in which a submissive will give money and gifts to a financial dominant.
Gonzo porn is like the professional version of amateur porn.
A conventional porn 'feature film' is usually a big production with plots, dialogue, and characters. Whereas 'no-frills' Gonzo is just all about the fucking.
Gonzo has become increasingly popular as it's cheaper to make, and often includes more intense sexual performances, lots of close ups and lengthier sex scenes.