Sometime in the last two or three years, WAN optimization moved from niche specialty to full-on focus area for many solution providers looking to broaden what they could offer customers for networking, infrastructure and data center solutions. That means competition in the WAN-op space will only continue to increase, with cloud-focused startup players like Aryaka Networks and mobile WAN-op specialists like Circadence drawing swords on top players like Riverbed Technology, and other WAN op strongholds like Blue Coat that despite their challenges are looking to get more of the action. And just how much action is that? Well, Gartner has WAN optimization growing from the $700 million market it was in 2006 to exiting 2011 at $1.9 billion, with projections of tenfold growth over the next five years. Cha-ching.