YouTube 3D does not support active shutter method of 3D stream viewing, e.g. nVIDIA 3D Vision in the window of the browser.
I have uploaded this 3D video to nVIDIA 3D Vision Live site. You are able to view in streaming manner with active shutter glasses on this site.

http://www.3dvisionlive.com/category/director/inouek3d

Using brand new nVIDIA 3DTV Play software in PC, you may be able to view this content in your 3DTV large screen.
Viewing downloaded file with stereoscopic player like Stereoscopic Player etc is another solutions.
———————————————————–
Direct link to YouTube 3D 1080P Full HD :

Direct link to YouTube 3D HD :

Original file : 1280×960 Over/Under 10Mbps wmv
Test using 3d video in Over/Under format with yt3d:left/right tags.
To view this video in 3D, select viewing style first from 12 option of drop down list box named “3D View Style”,
Red/cyan, amber/blue etc. requires 3D glasses.
Some other options, parallel and cross etc. doesn’t require any glasses. No viewing style with polarization type glasses like Real D is supported by YouTube 3D so far. 3D view style drop down menu may not appear unless using latest browser and player plug in.