I'll be actually participating in endgame content! It took me 5 years of off and on playing since WoW launched to finally see a character thru to the end game tier. The real motivation behind it probably was that I was tired of seeing patch notes or content updates and not getting to mess around with any of the fun mechanics!
Have to say that my shadow priest has definitely been one of the more enjoyable classes I've played. If I was playing a different class not sure how far I would have gone. The ability to melt faces, or put them back on, I think was a key factor. Plus everyone loves a healer!