Personally I (and my brothers) LOVED this year. The order in which the sets were released went perfectly with the storyline, with the Piraka and the Matoran being released first, and then finally the Toa Inika arrived to save the day. Much better than the heroes being just there, and the villains being released later like 04-05. The titan sets were epic, we ended up only getting Brutaka, but man, he was epic! It's still my dream to collect Vezon and Fenrakk. We did get Irnakk though, and the golden piraka head is also quite epic!
I also enjoyed the LEGO system sets that included the Toa and Piraka in minifigure size. My favorite was the Piraka Stronghold, lots of play function, the giant piraka head gate, and the spider chariot to name a few. The "minifigures" were a lot better than the -05 hordika figures too.
Storywise, it was epic. I loved the Piraka as villains, it was so nice having villains that weren't a part of a horde or swarm (the Kal don't count). They were their own masters and they were on a rampage. We collected all the books and waited with baited breath to receive the next comic edition to see what happened next. The introduction of the Mask of Life was really cool and it was epic seeing the Nuva back. I was even okay with how they were defeated by the Piraka, it just set up how powerful those guys were (even though it still hurts reading about their defeat...)
All in all, it was a great year!