I cared about achievements in Wrath and early Cataclysm but stopped caring a long time ago. Too many achievement points tied to shit I don't like doing or even find fun to bother anymore.
I basically never check achievements anymore and I could careless what people have. I can see maybe checking for PvP but PvE, not so much. Awhile back we recruited this mage with only like 4-5k achievement points and he was a better player / higher DPS than our 20k achievement mage during heroic progression.