Strong growth in display, video and mobile-based advertising prompted a banner year for U.S. online advertising as revenues topped $31 billion, a 22% jump over 2010 and a new record, according to the Interactive Advertising Bureau (IAB).

In terms of spending, retail continued to be the top category, accounting for 22% of all Internet ad spending. Next on the list was telecom (12%) and leisure/travel (8%). Meanwhile, Internet advertising is the second-biggest ad category next to television, which accounted for $38.5 billion of ad spending on 2011.

Mobile grew the most of all categories — 149% — but still represents a puny share of the overall market — $1.6 billion — according to the report issued on Wednesday. Digital video also rose 29% to $1.8 billion, search was up about 27% to $11.7 billion and display advertising jumped 15% to $11.1 billion, or 35% of all revenues. Search is still the largest category with 47% share.