Arbor started doing it a few years ago. A couple models of Stepchild boards have it now, as do a couple DC models. It's called a Structurn base. Arbors that friends and I owned with that base were all pretty fast. Not sure how much of the speed was from the sintered material used or this tech, but it definitely wasn't any kind of drawback.
18 Rossignol Sushi . 17 Arbor Terrapin . 17 Lib x Lost Mayhem Short Fat . 17 Capita Spring Break Slush Slasher . 16 Never Summer Swift . 14 TJ Brand Retro Fish
17 Union Ultra . 17 Rome Katana . 17 Burton Malavita Wing . 16 Burton Genesis X
16 Flow Talon