I thought I read all the major announcement sites, but it appears I missed a couple. I really do prefer reading from original sources. However, in reading a few sites I have seen the following hints:
According to Frostheim, http://www.warcrafthuntersunion.com/2012/03/mists-of-pandaria-press-tour,
· No more prime glyphs. They are being removed entirely, and we’re getting many more major and minor glyphs. Apparently there are several hunter major glyphs that used to be hunter talents; however, we don’t know which ones specifically.
· There will be 11 character slots, so you can have one of each class on the same server.
Rohan also had this article http://blessingofkings.blogspot.com.au/2012/03/bubble-hearth-returns.html, talking about some of the new pally glyphs.
Also I expect many players will delete alts and roll their favourite class as a panda.
When blizzard adds only a glyph or two, dedicated scribes grab them quickly and flood the market with them. However, if there are a lot of glyphs being added, providing they are not trainer taught, it will keep me gainfully employed.
Good news for scribes in the days to come.