Though already a multi-billion dollar market in Asia, virtual goods are just beginning to grow as a primary game monetization model in the United States. But what’s the market size today?

According to data from a recent report by Piper Jaffray, US virtual goods revenue last year came it at only around $265 million. PJC is calling for a 134% increase in 2009 to $621 million. The report also estimates  that the growth will remain in the double digits until 2013, at which point total virtual goods revenues will be about $2.5 billion.

While the report points out that a majority of virtual goods’ sales came from virtual worlds, the report says more are shifting to social networks. In general, however, we think these numbers are quite low for 2009 and 2010. Numbers we’re hearing are pointing to much stronger figures.

Piper Jaffray expects global revenues to reach more than $2.2 billion this year. However, in April, +8* | Plus Eight Star, an Asian market research firm, estimated that Asia’s virtual goods economy alone might be worth more than $5 billion. Piper Jaffray expects global revenues to surpass $6 billion come 2013.