If you use the Auction Profit Master addon to speed post glyphs then you are familiar with the fallback setting. What the fallback is, is when there are auctions posted in the AH that are less then the minimum you are willing to post for APM will automatically post your glyph at your fallback price.
for example: my threshold (minimun im willing to post at) is set to 15g, Whenever someone has posted an auction that is under 15g apm will post my glyph for 75g (my fallback). What this can do is greatly raies the price of the glyph... when all those glyphs sell you will be the one who determines what the market starts at.
This technique is most effective when almost your entire glyph market (meaning the other posters) follow the same settings as you. I posted earlier about the whitelist and how you should have joined a group by now, well now is the time to discuss your new fallback price with them. My group has come to the agreement to double our fallback price to 150g for cataclysm because the large boom of new players needing new glyphs will quickly outmatch the supply of glyphs.
In todays economics companys deal with shortages by raising prices, and this is what your fallback will do for you. I also suggest that on monday night you post roughly 4+ of each glyph at your fallback price and also for 48 hours. You never know what will happen when a new xpac comes in so you want to make sure that your glyphs and/or everything else you need to post are still on the auction house if servers take a while to come onlne.
My final advise for glyphers is that flooding the market before an expansion (at high prices) isnt a bad thing at all. What is bad is posting your glyphs at too low of a price because there is always the possibility that all of your competition will post before the surge of sales happens and you dont want to start the xpac off with a low profit margin.