The Cataclysm has hit, and that brings changes for not only max level characters, but low level toons as well. Blizzard went through their quests with a fine-tooth comb, and marked oodles of them obsolete, and can't be obtained or completed. This is a very good thing, don't get me wrong.
However, hidden among the hundreds of "kill 10 rats, come back, turn it in, go back to the exact same spot and kill 10 Elder rats" type of quests were some quests that I had come to rely on at certain levels for fast XP and sometimes rep.
Wool (12), Silk (26), Mageweave (40), and Runecloth (50) turnins are gone. At those levels, my toons would make the rounds of the capitol cities, turning in 60 pieces of cloth to 5 different NPC's, and gaining a good chunk of rep and XP in the process. Those NPC's are now goooooone. Sell your stockpiles of cloth, use them in Tailoring or First Aid, but you can't use them for rep anymore.
Next up, we have a quest located in one of the busiest ganking spots on a PvP server, Stranglethorn Vale. It used to take 14 seperate pages to do all the quests needed for the Green Hills of Stranglethorn Vale, now it only takes 1 page. Sell any and all pages in your bank, even old page 14 won't work for the new quest.
Blasted Lands had about 5 quests with extremely low drop rate quest items, doable at level 45. It was a nice XP boost if you did it right at 45, bringing you almost to 46 if I remember correctly. Basilisk Brain, Blasted Boar Lung, Scorpok Pincer, Snickerfang Jowl, and Vulture Gizzard were all needed to finish the quests, in varying amounts. The Vulture Gizzard drops were particularly horrendous. Toss them, you can't sell them. Here's an example of how many I had saved up, on my baby Horde server Darrowmere.
And finally, Argent Dawn rep. I wanted rep with factions as soon as it was possible, and I wasn't high enough to solo instances yet, so I started collecting the quest items. Dark Iron Scraps, Bone Fragments, Crypt Fiend Parts, Core of Elements, Savage Frond.....I collected them all from the AH, when they had a low bid of a few silver for several. Sell them, you can't do anything with them.
Anyone wanna buy some Dark Iron Scraps?
Surprisingly, the Craftsman's Writ quests, even though marked in Wowhead as obsolete, CAN be still completed if you have the writ and items needed. My warrior Bullkathos did the Stonescale Eel one last night, and instead of being given the choice between Insignia of the Dawn or Insignia of the Crusade, he just got a straight 150 rep. Dump the Insignia's btw, you can't redeem them anymore.
Am I mad that Blizzard got rid of these quests, making the items useless? Hell no! I'm glad that we no longer have quests that require 12 raptor heads, and all the raptors you kill in the Barrens seem to be headless. Random Number Generator items should be on important stuff, like Rivendare's mount. It shouldn't take an hour to do one simple quest, and Blizzard finally recognized that.