Let me first say, pre-BC, I didn't really raid. I did ZG four or five times, other than that nothing. So, I had never tried Onyxia nor had Cait and Bucky. So, our group make-up was Moonkin (Delos), Survival Hunter (me), Resto Druid (Cait) and Protection Paladin (Bucky).
So, we killed her (yay) on our third try! The first two tried we had MANY WHELPS! by mistake (Ony noobs, aye). regardless, we killed her!! Some things that were quite annoying: 1) her agro table seemed random and we all kept pulling her without actually taking lead on threat (omen). Also, I did not bring consumable, which OMG was that a mistake. If Bucky didn't judge wisdom we would never have done it. So, good times from the past times of 40-man content. One awesome thing to note: 32g each from her! Also, tons of DE items and blues to sell on the AH. If we can farm her, that would be a great income source! :)
It was one of the more enjoyable nights of WoW I have had in a while!
Also, we killed Hydross in my guild raid!!