[@Bishop]I though like that about the first filler season (the one that ended Naruto, before Shippuuden). Some of those fillers were really good, some were bad... I stopped watching the series some time into shippuuden when they started to get too friendly with the filler again and picked up the manga instead. For all it is and isn't, there is very little filler. 
Anyway, now that the show is finished (is the anime finished as well?) I have heard that in the end they started spreading the flashback-fillers on really thick, someone claimed that it was kind of like watching the whole series a second time. That's why I thought it best to keep the spoilers to a minimum.