It took 40 people to complete a raid in vanilla. That is a lot of gearing time, and a lot of prep.
It takes 10 people to do a raid in Cataclysm. You can also do raids through LFR (lol easy practice mode). In Vanilla, Rag was not the first raid end boss. There were many other before him. Deathwing was the only end boss of this patch. It took about 1 month for people to kill heroic Deathwing, which is certainly long enough in my mind. Hell, to date, only 90 guilds have killed him on heroic.