Well, they have made these mistakes in the past, however I usually was too late with these kind of things in the past and they got hotfixed. :P

Guilt? No. The market is already destroyed by all the bank sellers in anticipation of WotLK. Endgame is making a shift, and just like back when 60-70, prices are AWOL at the moment. That's why I suggest selling low, quick and big amounts, or keep the shards a few months and hope they'll be orth more once wotlk market balances. However, Large Brilliant Shards never got expensive, Greater Eternal did, but this is about farming epics so, yeah, get rid of the shards asap. Always someone thinking to make a buck if you sell like 200 LPS's for 7g a piece or cheaper then anything on the AH anyhow. Tbh, they probably won't, because by the time they got rid of the 200 shards, it will be a few months from now. :P

Normally Blizz fixes these kinda things within a few days, I find it remarkable this hasn't changed yet in all honesty.