I've read many posts recently about being heroic ready and I've followed the advice given. I'm sitting at 495 def, 11.6k armor, 11.4k HP unbuffed and a combined avoidance of 32%. So last night with the new daily quest calling for an item from Blood Furnace, I figured I'd give it a shot. This was my first heroic run and I was a bit nervous to say the least. Nonetheless we were able to make it to the second boss without a wipe and only one death due to our shadow priest nuking a mob and stealing aggro.
At this point our healer, a resto druid, experienced lag and ended up DC'ing causing a wipe. We replaced her with a shammy who could heal but was more interested in dishing out DPS. To make a long story short, we didn't make it much further.
The point of this thread is, if you have the base stats recommended for heroics, then you are ready. I proved this to myself last night. I will say that party communication is key and everyone must be doing their job. I never really took this into account until last night, as I've run instances where the healers did take some time to DPS when the going was good.
I also want to add that with the new patch having lowered the rep required for heroic keys, be wary of who you run with. I had several people wearing mostly greens ask me to tank last night and a rogue friend of mine couldn't get his group past the first room because the people he was running with were undergeared.
Anyways, good luck to everyone in their heroic endeavors and remember to have fun.