I think 2boys_jademommy was right about the interchangeability of the terms glassy and icy. Icy jadeite, however, is the more common term because most jadeite products available on the market now are from waxy-icy (冰糯) to high-icy (高冰). A piece of jadeite can only be called "glassy" if and only if you can place the jade on a piece of newspaper and still be able to literally see the letters behind the jade. Notice I said "see" but not "read." This is because for floating-green glassy jadeite 8mm thick or above, you can only merely make out the general shapes of the letters, but not clearly enough to be able to "read" the text.
As for nephrite jade, I think green nephrite is in vogue nowadays. Green Russian nephrite is generally better than Canadian nephrite. For white nephrite, however, the best comes from Hetian in Xinjiang of China. Hence the name Hetian jade.
For many foreign jade lovers, jadeite has a more intrinsic beauty in itself. For Chinese Jade lovers, Hetian jade has cultural-historical value--one that is over 7000 years old. Jadeite rewards the eye with its watery, glassy sheen. Hetian jade rewards the touch with its soft-and-smooth-as-baby-skin feel. Jadeite has many colors (even on the same piece) for the artist-carvers to explore and put to great artistic use. Hetian jade forces the artist-carvers to embrace strict conventions and formalism. In short, it's a modernity versus antiquity sort of case.
Just a warning though, trying to buy the real Hetian jade (meaning jade mined in Hetian) is a brave attempt. There's hardly any official methods to verify origin. Testing centers in China will unscrupulously put "Hetian jade" on any kinds of white nephrite (whether they come from Hetian, Russia, Korea, or Qinghai). Sellers use this ambiguity to trick buyers, telling them the jade is from Hetian to inflate prices. However, that doesn't mean all hopes are lost. I am now doing research on reliable Hetian jade sellers. I will keep you guys updated if anyone is interested.
Thank you Henry James for that wealth of information. Really enjoyed reading your post

A lot of sellers do use the word Hetian to inflate the cost of nephrite regardless of where the stone came from. Same as saying jadeite is from Burma regardless of its origin. I believe though that the Nephrite from Siberia has been gaining much recognition and respect for its beauty in recent years.