Heirloom item levels are bugged and either indicating 0 item level for those items or a much lower ilvl. I cannot queue for RDF with my 82 DK for cata dungeons even though they were queuing for them before this patch. It says they have a ilvl of 135 when the requirement is 220+. They are using all heirlooms and random wrath epics + cata blues for the other slots.
I also have a 84 priest and 83 Warlock that can only queue for the first two Cata dungeons when they were queuing for all of the available ones before the patch. Same thing with gear. Mostly heirlooms with wrath epics + cata blues.