Email Security Appliances Are Popular ... for Now. As part of the current market churn, email security appliances are enjoying increased popularity relative to software and hosted service providers. This faster growth will continue for a while. By 2007, however, most customers who are switching to appliances will have done so, and this segment will stabilize at about one-quarter of the market, growing at the same rate as software and hosted service providers.

In other words, the current growth spurt is caused by churn. Some organizations that are replacing failing email security software see their problems as partly architectural, so they are switching to an appliance architecture (from software).

This is from our recent report, The Email Security Market, 2005-2010. ... Richi Jennings