You say that like Naxx is equivalent to Sunwell. It isn't.
Naxx is the equivalent level of Karazhan was in TBC, the beginning raid instance, only Blizzard have made it more accessible to more people by doing 10 and 25 man versions, made bosses easier than expected, and provided better access to the equipment necessary to prepare for Naxxramas.
Trust me, Naxx is far from being a pipe dream for a large number of average gamers. Sure, they're not going to clear it out in 2 days like 25thNovember/Ensidia did, but that still doesn't mean it's going to be a brick wall in endgame like you think...
I guess as I should have said as far as current content goes,,,for the casual gamer that never got to Sunwell the prof's look fantastic, and I'm sure that with the new patch (ie like sun) there will be patterns far more epic than now. Sunwell crafted gear is still some of the best if you look at maxdps.com but will fall quickly behind when the next patch hits...lol..probably.