Woah, you are right! I just checked my Chrome task manager (Shift+Esc on Linux). It is never less than 50% CPU at top of page in 3D mode. If I scroll, it jumps to > 100% CPU! The tab is using 250MB of RAM. And to think I am working on a ridiculously over-powered workstation w/ 3.8 GHz cores & 4K screens!