Season 1: Spectacular season to start off the series. Didn't quite have the adult-humored style that the next two seasons had, but it was still very creative. I also love the classic cel-animation that was only used in this season. 9.1/10
Favorite episode: Scaredy Pants
Least favorite episode: Neptune's Spatula
Season 2: This is my favorite season of all-time. The jokes were very clever and the show managed to still be a kid-friendly show while appealing largely to adults as well with its dialogue. In fact, the beginning of the whole SpongeBob worldwide phenomenon began while this season was airing. The animation in the beginning half was a bit crude, however (they probably were still making the transition from traditional to digital ink-and-paint), but it soon improved. 9.8/10
Favorite episode: Band Geeks
Least favorite episode: Squid on Strike
Season 3: Finally, the last batch of the so-called "golden episodes" of SpongeBob. The show was pretty much at its grand peak when this season came out. I always looked forward to tuning in to whatever new episode was coming on and I was never disappointed. The animation was good and all, but I kinda find it a little too vibrant. I guess once they figured out how to use digital ink-and-paint, they ended up using too much of it.
Plus, there were some times when the humor tended to be a bit too monotonous, but in a rare way, superb (I can see a lot of this with C.H. Greenblatt's show "Chowder"). 9.6/10
Favorite episode: SpongeBob's House Party
Least favorite episode: Can You Spare a Dime?
Season 4: Although this was probably the most criticized season at the time when it was airing, as I look back at it, it had some really good episodes. Of course, this was when the majority of the show's longtime writers moved on to other projects, so it had many newbie writers who, I would say, were still trying to adjust. The animation, however, was sub-par. It wasn't until about the last four episodes when the animation finally improved to the permanent style that's still being used in today's newest episodes. Overall, this season wasn't really that good, but it didn't wreak so bad (despite it being the worst season on my list). 7.4/10
Favorite episode: Have You Seen This Snail?
Least favorite episode: Hocus Pocus (just because my icon comes from that episode, doesn't mean I liked it)
Season 5: When this season started (with the exception of "Friend or Foe", "Rise and Shine", and "Waiting" which I didn't really like) it turned out to be a very good comeback. However, towards the second half, the season seemed to take a, what some may consider, massive plunge in terms of plot qualities. They were just too crazy and the humor had a tendency to be too childish. All in all, it was a good season at first, but turned out to be a bit of a disappointment. 7.9/10
Favorite episode: Roller Cowards
Least favorite episode: Waiting
Season 6: While this season turned out to be a bit better than the last two, it was still making the transition out from Season 5's quality. It pretty much flip-flopped between really good and really bad episodes. I personally blame Aaron Springer, who's supposedly been the "cartoon genius" since the show's beginning, for some of those bad episodes. However, like season 4, it sort of got better towards the end. 8.4/10
Favorite episode: Not Normal
Least favorite episode: Penny Foolish
Season 7: Now, we get to the current season. Some users say that this season is overrated, but I on the other hand think it's getting just the right praise it deserves. Like I've said in another thread, many of the plots seem lame when you first hear about them, but when you actually watch the episodes, they turn out to be much better than you expected. Sure, you can disagree with me *coughshipeoplescoughs* but I think this is a spectacular season and I'm looking forward to see what else they have in store. 8.9/10
Favorite episode: Tentacle-Vision
Least favorite episode: Shell Shocked
Phew! Boy, did I spend a lot of time writing that.