Like the Internet before it, it looks like mobile’s content explosion could be set off by porn. Adult content on mobile devices will be worth $3.3 billion by 2011, up from $1.4 billion this year, according to industry analysts Juniper Research.

Europe is the biggest spender on porn, due to both its appetite for smut and the relatively high-priced nature of adult content. The Asia-Pacific region follows in second place.

The development of the adult content market will also evolve in parallel with mobile telephony technology, Juniper predicted. Currently, most adult content is text-based. As 3G wireless, which provides more capacity for multimedia services, reaches maturity, porn will switch to video delivery, Juniper said. More than 70 percent of revenue will be derived from that medium by 2011, according to the report.