If by liquid, you mean something that can flow (even over an extremely long time frame) and has propery of viscosity, then glass at room temperature is NOT a liquid. It's not really a solid, either, however.

The antique window-pane evidence often used to support the idea that glass is a liquid has been shown to be untrue.

Check out these sites:

http://math.ucr.edu/home/baez/physics/General/Glass/glass.html
http://www.spectrumglass.com/Library/ScoreArticles/BitAboutGlass.html
http://www.newton.dep.anl.gov/askasci/chem99/chem99017.htm