dude i dont even have Mists yet. the money just isnt there for me. im much more behind than you. yet i still play. im enjoying pet battles currently and i have lots of reasons to log in everyday. its just fun! play for the reason you like, not for what others think.
I have raided with most of the same people since classic or Burning Crusade. Every expansion, we start raiding a month or two after launch. We have a lot of people in the guild with demanding careers or young children or both who usually only get an hour or two a night to play (and not every night of the week). It usually takes them several weeks just to reach the cap, nevermind the time it takes to gear up. On top of that, usually the expansions drop right around winter holidays when people are out of town or busy, further slowing things down. By the time everyone is settled and ready, the best raids are already farming the content on heroic.
Obviously we're not getting server firsts, but over the course of the tier we keep up with other raids who raid similar amounts even though they've started earlier. And while I don't think most raids start as late as us, plenty of raid groups aren't jumping into raiding the very first week.
And by the second tier, that late start is irrelevant. We all venture in the same week.