As the battle between active and passive 3D glasses display technology heats up, Samsung has responded by announcing its cheapest pair of active shutter 3D glasses will cost $50 (previously $130) beginning May 1st. Additionally, all of its 3D-capable 2011 HDTVs will come with two pairs of glasses packed in, unless the purchase is eligible for the Megamind / Shrek starter kit that already comes with them. This move comes just as FPR-based displays from LG, Vizio, Toshiba and Philips hit the marketplace. LG specifically focused on the cost of glasses as a selling point over Samsung in recent ads that ran heavily throughout the NCAA Tournament (embedded after the break.) LG is charging $10 per pair for its RealD-compatible Theater 3D glasses while Vizio has pairs on its website for $29.99 or two for $44.99. The cheap pair of Samsung glasses is the SSG-3100GB model with replaceable battery pictured above and while it promises the new, lighter Silhouette-designed SSG-3700GR gl...